Disc Brakes

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‌BRAKES

Disc Brakes - Volt

SPECIFICATIONS

FASTENER SPECIFICATIONS

Single Use Non-Threaded Fasteners/Components

NOTE:

All fasteners/components listed in this table MUST BE DISCARDED and

replaced with NEW after removal.

Application

Brake Hose Fitting Gasket

Brake Caliper Dust Boot Seal

Brake Caliper Piston Seal

Single Use Threaded Fastener/Component Tightening Specifications

NOTE: All fasteners/components listed in this table MUST BE DISCARDED and replaced with NEW after removal.
Application	Specification
Application	Metric (English)
Brake Caliper Guide Pin Bolt - Front	40 N.m (30 lb ft)
Brake Caliper Guide Pin Bolt - Rear	36 N.m (27 lb ft)

Reusable Threaded Fastener Tightening Specifications

NOTE: All fasteners listed in this table can be reused after removal.
Application	Specification
Application	Metric (English)
Brake Caliper Bleeder Valve - Front	10 N.m (89 lb in)
Brake Caliper Bleeder Valve - Rear	13 N.m (115 lb in)

NOTE: All fasteners listed in this table can be reused after removal.
Application	Specification
Application	Metric (English)
Brake Caliper Bracket Bolt - Front
First Pass:	150 N.m (111 lb ft)
Final Pass:	15-30 Degrees
Brake Caliper Bracket Bolt - Rear
First Pass:	100 N.m (74 lb ft)
Final Pass:	15-30 Degrees
Brake Hose Fitting Bolt - Front and Rear	40 N.m (30 lb ft)
Brake Rotor Bolt - Front and Rear	9 N.m (80 lb in)
Shock Absorber Bolt	100 N.m (74 lb ft)
Wheel Bearing and Hub Assembly - Rear
First Pass:	50 N.m (37 lb ft)
Final Pass:	30-45 Degrees

DISC BRAKE COMPONENT SPECIFICATIONS

Application	Specification
Application	Metric	English
Front Brakes
Caliper Bore Diameter-Front (15" Brake System) (J67)	60 mm	2.362 in
Rotor Diameter (15" Brake System) (J67)	276 mm	10.866 in
Rotor Thickness (15" Brake System) (J67)	26 mm	1.024 in
Rotor Discard Thickness (15" Brake System) (J67)	23 mm	0.906 in
Rotor Maximum Allowable Assembled Lateral Runout (15" Brake System) (J67)	0.04 mm	0.0016 in
Rotor Maximum Allowable Scoring (15" Brake System) (J67)	0.4 mm	0.0158 in

Application	Specification
Application	Metric	English
Rotor Minimum Allowable Thickness After Refinish (15" Brake System) (J67)	23.2 mm	0.9134 in
Rotor Maximum Allowable Thickness Variation (15" Brake System) (J67)	0.006 mm	0.0002 in
Brake Pad Thickness New without Pad Plate	11.4 mm	0.449 in
Brake Pad Discard Thickness without Pad Plate	2 mm	0.079 in
Rear Brakes
Caliper Bore Diameter-Rear (15" Brake System)	38 mm	1.496 in
Rotor Diameter (15" Brake System)	264 mm	10.394 in
Rotor Thickness (15" Brake System)	10 mm	0.394 in
Rotor Discard Thickness (15" Brake System)	8 mm	0.315 in
Rotor Maximum Allowable Assembled Lateral Runout (15" Brake System)	0.04 mm	0.0016 in
Rotor Maximum Allowable Scoring (15" Brake System)	0.4 mm	0.0157 in
Rotor Minimum Allowable Thickness After Refinish (15" Brake System)	8.2 mm	0.323 in
Rotor Maximum Allowable Thickness Variation (15" Brake System)	0.006 mm	0.0002 in
Brake Pad Thickness New without Pad Plate	10 mm	0.394 in
Brake Pad Discard Thickness without Pad Plate	2 mm	0.079 in

ADHESIVES, FLUIDS, LUBRICANTS, AND SEALERS

Application

Type of Material

GM Part Number

United States

Canada

Hydraulic Brake System

DOT 3 Motor Vehicle Brake

Fluid

19299818

19299819

DIAGNOSTIC INFORMATION AND PROCEDURES

BRAKE ROTOR THICKNESS MEASUREMENT

Special Tools

CH-230-A Disc Gauge

Equivalent regional tools: Special Tools

WARNING: Refer to Brake Dust Warning .

Fig. 1: Disc Gauge On Brake Rotor

Courtesy of GENERAL MOTORS COMPANY

1. If the inboard friction surface of the brake rotor is not accessible, remove the brake pads. Refer to Front Disc Brake Pads Replacement, and/or Rear Disc Brake Pads Replacement, if equipped.

2. Clean the friction surfaces of the brake rotor with denatured alcohol, or an equivalent approved brake cleaner.

NOTE: Ensure the measurements are only taken within the friction surfaces.

3. Install the CH-230-A gauge for lateral runout measurement.

1. Measure and record the thickness of the brake rotor at 4 or more points from the brake rotor inside to

outside.

2. Compare the lowest thickness measurement to the disc brake component specifications. Refer to Disc Brake Component Specifications.

4. If the lowest thickness measurement of the brake rotor is above the minimum allowable thickness after refinishing specification, the rotor may be able to be refinished, depending upon surface and wear conditions which may be present.

5. If the lowest thickness measurement of the brake rotor is at or below the minimum allowable thickness after refinishing specification, the rotor may not be refinished.

6. If the lowest thickness measurement of the brake rotor is at or below the discard thickness specification, the rotor requires replacement. Refer to Front Brake Rotor Replacement, and/or Rear Brake Rotor Replacement.

BRAKE ROTOR THICKNESS VARIATION MEASUREMENT

Special Tools

CH-45101 Hub and Wheel Runout Gauge

For equivalent regional tools, refer to Special Tools.

WARNING: Refer to Brake Dust Warning .

NOTE: Any disc brake rotor that exhibits thickness variation exceeding the maximum acceptable level must be refinished or replaced. Thickness variation exceeding the maximum acceptable level can cause brake pulsation.

1. If the inboard friction surface of the brake rotor is not accessible, remove the brake pads. Refer to Front Disc Brake Pads Replacement, and/or Rear Disc Brake Pads Replacement, if equipped.

2. Clean the friction surfaces of the brake rotor with denatured alcohol, or an equivalent approved brake cleaner.

Fig. 2: Mounting Dial Indicator To Measure Lateral Runout Courtesy of GENERAL MOTORS COMPANY

NOTE: Ensure the measurements are only taken within the friction surfaces.

3. Install the CH-45101 runout gauge for lateral runout measurement and compare with the correct specifications. Refer to Disc Brake Component Specifications.

NOTE: Whenever a brake rotor is refinished or replaced, the assembled lateral runout (LRO) of the rotor must be measured to ensure optimum performance of the disc brakes.

4. If the brake rotor lateral runout measurement exceeds the specification, the rotor requires refinishing or replacement. Refer to Front Brake Rotor Replacement, Rear Brake Rotor Replacement, or Brake Rotor Refinishing.

BRAKE ROTOR SURFACE AND WEAR INSPECTION

WARNING: Refer to Brake Dust Warning .

1. If the inboard friction surface of the brake rotor is not accessible, remove the brake pads. Refer to Front Disc Brake Pads Replacement, or/and Rear Disc Brake Pads Replacement.

2. Clean the friction surfaces of the brake rotor with denatured alcohol, or an equivalent approved brake cleaner.

3. Inspect the friction surfaces of the brake rotor for the following Braking Surface Conditions: Heavy rust and/or pitting.

Light surface rust can be removed with an abrasive disc. Heavy surface rust and/or pitting must be removed by refinishing the rotor. Refer to Brake Rotor Refinishing .

Cracks and/or heat spots.

Excessive bluing discoloration.

4. If the friction surfaces of the brake rotor exhibit one or more of the Braking Surface Conditions, the rotor requires refinishing or replacement. Refer to Front Brake Rotor Replacement, Rear Brake Rotor Replacement, or Brake Rotor Refinishing.

BRAKE ROTOR ASSEMBLED LATERAL RUNOUT MEASUREMENT

Special Tools

CH-41013 Rotor Resurfacing Kit

CH-42450-A Wheel Hub Resurfacing Kit

CH-45101 Hub and Wheel Runout Gauge

CH-45101-100 Conical Brake Rotor Washers

For equivalent regional tool, refer to Special Tools.

WARNING: Refer to Brake Dust Warning .

NOTE: Brake rotor assembled lateral runout (LRO) exceeding the maximum allowable specification can cause thickness variation to develop in the brake rotor over time, usually between 4800 and 11300 km (3000 and 7000 mi).

Brake rotor thickness variation MUST be checked BEFORE checking for assembled lateral runout (LRO). Thickness variation exceeding the maximum acceptable level can cause brake pulsation. Refer to Brake Rotor Thickness Variation Measurement.

NOTE: Whenever the brake rotor has been separated from the hub/axle flange, any rust or contaminants should be cleaned from the hub/axle flange and the brake rotor mating surfaces. Failure to do this may result in excessive assembled lateral runout (LRO) of the brake rotor, which could lead to brake pulsation.

1. Inspect the mating surface of the hub/axle flange and the brake rotor to ensure that there are no foreign particles, corrosion, rust, or debris remaining. If the wheel hub/axle flange and/or if the brake rotor mating surfaces exhibit these conditions, perform the following steps:

1. Remove the brake rotor from the vehicle. Refer to Front Brake Rotor Replacement, and/or Rear Brake Rotor Replacement.

2. Using the CH-42450-A resurfacing kit, thoroughly clean any rust or corrosion from the mating surface of the hub/axle flange.

3. Using the CH-41013 resurfacing kit, thoroughly clean any rust or corrosion from the mating surface of the brake rotor.

4. Clean the friction surfaces of the brake rotor with denatured alcohol, or an equivalent approved brake cleaner.

2. Install the rotor to the hub/axle flange.

Fig. 3: Conical Brake Rotor Washer And Lug Nut Courtesy of GENERAL MOTORS COMPANY

3. Hold the rotor firmly in place against the hub/axle flange and install one of the CH-45101-100 washers (1), and one lug nut (2) onto the upper-most wheel stud.

4. Continue to hold the rotor secure and tighten the lug nut firmly by hand.

Fig. 4: Conical Brake Rotor Washers And Lug Nuts Courtesy of GENERAL MOTORS COMPANY

5. Install the remaining CH-45101-100 washers (1) and lug nuts onto the wheel studs and tighten the nuts firmly by hand in a star-pattern.

6. Tighten the lug nuts in a star-pattern to specification, in order to properly secure the rotor. Refer to Tire and Wheel Removal and Installation .

7. If the brake rotor has been REFINISHED or REPLACED with a new rotor, proceed to step 13.

8. If the brake rotor meets the following criteria, proceed to step 9. The rotor is within specifications and is being REUSED. The rotor has NOT been refinished.

The rotor does NOT exhibit thickness variation exceeding the maximum allowable level.

Fig. 5: Measuring Brake Rotor Lateral Runout Courtesy of GENERAL MOTORS COMPANY

9. Mount the CH-45101 gauge (1) or equivalent, to the strut and position the indicator button so it contacts the brake rotor friction surface at a 90 degree angle, approximately 13 mm (0.5 in) from the outer edge of the rotor.

10. Measure and record the assembled LRO of the brake rotor.

1. Rotate the rotor until the lowest reading is displayed on the indicator dial, then set the dial to zero.

2. Rotate the rotor until the highest reading is displayed on the dial.

3. Mark the location of the high spot relative to the nearest wheel stud, or studs.

4. Measure and record the amount of LRO.

11. Compare the brake rotor assembled LRO to the disc brake component specifications. Refer to Disc Brake Component Specifications

12. If the brake rotor assembled LRO is within specifications, proceed to step 17.

If the brake rotor assembled LRO exceeds the specification, refinish the rotor to ensure true parallelism. Refer to Brake Rotor Refinishing. After refinishing the rotor, proceed to step 13.

13. Mount the CH-45101 gauge (1) or equivalent, to the strut and position the indicator button so it contacts the

brake rotor friction surface at a 90 degree angle, approximately 13 mm (0.5 in) from the outer edge of the rotor.

14. Measure and record the assembled LRO of the brake rotor.

1. Rotate the rotor until the lowest reading is displayed on the indicator dial, then set the dial to zero.

2. Rotate the rotor until the highest reading is displayed on the dial.

3. Mark the location of the high spot relative to the nearest wheel stud, or studs.

4. Measure and record the amount of LRO.

15. Compare the brake rotor assembled LRO to the disc brake component specifications.

16. If the brake rotor assembled LRO measurement exceeds the specification, replace the brake rotors. Refer to

Front Brake Rotor Replacement, and/or Rear Brake Rotor Replacement.

17. If the brake rotor assembled LRO measurement is within specification, install the brake caliper and depress the brake pedal several times to secure the rotor in place before removing the CH-45101-100 washers.

BRAKE PAD INSPECTION

Special Tools

CH-230-A Disc Gauge

For equivalent regional tools, refer to Special Tools.

WARNING: Refer to Brake Dust Warning .

1. Remove brake pads. Refer to Front Disc Brake Pads Replacement, and/or Rear Disc Brake Pads Replacement.

Fig. 6: Measuring Brake Pad Thickness Courtesy of GENERAL MOTORS COMPANY

2. Measure remaining brake pad thickness at several points, using the CH-230-A disc gauge (1).

3. Compare brake pad thickness to disc brake component specifications.

BRAKE CALIPER INSPECTION

Fig. 7: Brake Caliper Components

Courtesy of GENERAL MOTORS COMPANY

WARNING: Refer to Brake Dust Warning .

1. Inspect the brake caliper housing (1) for cracks, excess wear, and/or damage. If any of these conditions are present, the brake caliper requires replacement.

2. Inspect the caliper piston dust boot seal (2) for cracks, tears, cuts, deterioration and/or improper seating in the caliper body. If any of these conditions are present, the brake caliper requires overhaul or replacement.

3. Inspect for brake fluid leakage around the caliper piston dust boot seal (2) and on the disc brake pads. If there is any evidence of brake fluid leakage, the brake caliper requires overhaul or replacement.

Fig. 8: Compressing Caliper Piston

Courtesy of GENERAL MOTORS COMPANY

4. Inspect for smooth and complete travel of the caliper pistons into the caliper bores:

The movement of the caliper pistons into the caliper bores should be smooth and even. If the caliper piston is frozen or difficult to bottom, the caliper requires overhaul or replacement.

For single piston caliper applications, insert a discarded inner brake pad (2) or block of wood in front of the piston. Using a large C-clamp (1) installed over the body of the caliper (3) and against the brake pad or block of wood, slowly bottom the piston in the bore.

For dual piston caliper applications, insert a discarded inner brake pad (2) or block of wood in front of the pistons. Using 2 large C-clamps (1) installed over the body of the caliper (3) and against the brake pad or block of wood, slowly bottom the pistons evenly into the bores.

FRONT DISC BRAKE MOUNTING AND HARDWARE INSPECTION

WARNING: Refer to Brake Dust Warning .

Fig. 9: Exploded View Of Brake Pads And Brake Caliper Mounting Bracket Courtesy of GENERAL MOTORS COMPANY

1. Inspect the fluid level in the brake master cylinder reservoir.

2. If the brake fluid level is midway between the maximum-full point and the minimum allowable level then no brake fluid needs to be removed from the reservoir before proceeding.

3. If the brake fluid level is higher than midway between the maximum-full point and the minimum allowable level then remove brake fluid to the midway point before proceeding.

4. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .

5. Remove the tire and wheel assembly. Refer to Tire and Wheel Removal and Installation .

6. Grasp the brake caliper housing and try to move the brake caliper housing up/down and forward/reverse in relation to the brake caliper mounting bracket (3). If excessive looseness is observed the brake caliper bracket bushings and/or the brake caliper mounting bolts may need to be replaced. Compress the front caliper pistons

7. Compress the front caliper pistons.

1. Install a large C-clamp over the top of the caliper housing and against the back of the outboard pad (1).

2. Slowly tighten the C-clamp until the pistons are pushed completely into the caliper bores.

3. Remove the C-clamp from the caliper.

8. With the pistons compressed into the caliper bores, grasp the brake caliper housing and slide it back and forth

on the brake caliper mounting bolts. Check for smooth operation. If the brake caliper housing slide force is high or the brake caliper housing does not slide smoothly, inspect the brake caliper mounting bolts and/or the brake caliper mounting bracket bushings for wear or damage. If wear or damage conditions are found, replacement of the brake caliper mounting bolts and/or the brake caliper mounting bracket bushings is necessary.

9. Remove the brake caliper mounting bolts from the brake caliper mounting bracket and support the brake caliper using heavy mechanics wire. Do Not remove the hydraulic brake hose from the caliper. Refer to Front Brake Caliper Replacement.

10. Remove the disc brake pads (1, 2) from the brake caliper mounting bracket (3).

11. Inspect the disc brake pad mounting hardware for the following: Missing mounting hardware.

Excessive corrosion.

Bent pad retainer spring (2).

Looseness at the brake caliper mounting bracket (3). Looseness at the disc brake pads (1, 4).

Excessive contaminants in the brake caliper mounting bracket (3) surface and threads.

12. If any of the conditions listed are found, the disc brake pad mounting hardware requires replacement.

13. Ensure the disc brake pads are held firmly in place on the brake caliper mounting bracket, yet slide easily on the mounting hardware without binding.

Fig. 10: Caliper, Guide Pin Bolt, Caliper Mounting Bracket And Guide Pin Seal/Boot Courtesy of GENERAL MOTORS COMPANY

14. Inspect the brake caliper mounting hardware for the following: Binding

Seizing

Looseness in the brake caliper mounting bracket (3). Bent or damaged brake caliper mounting bolts (1).

Cracked or torn boots (4). Missing boots.

Bent or damaged brake caliper mounting bracket (3). Cracked or damaged brake caliper (2).

15. If any of the conditions listed are found then the brake caliper mounting hardware requires replacement.

16. Install the disc brake pads to the brake caliper mounting bracket.

17. Install the disc brake caliper to the brake caliper mounting bracket. Refer to Front Brake Caliper Replacement.

REAR DISC BRAKE MOUNTING AND HARDWARE INSPECTION

WARNING: Brake Dust Warning

1. Remove Rear Brake Caliper Bracket. Refer to Rear Brake Caliper Bracket Replacement

Fig. 11: Exploded View Of Brake Pads And Brake Caliper Mounting Bracket Courtesy of GENERAL MOTORS COMPANY

2. Remove the disc brake caliper from the caliper mounting bracket (2).

3. Remove the disc brake pads (1) from the caliper mounting bracket (2).

4. Inspect the disc brake pad mounting hardware (3) (if installed) for the following: Missing mounting hardware.

Excessive corrosion.

Brake pad fastener spring is bent.

Looseness at the brake caliper mounting bracket. Looseness at the disc brake pads.

Excessive contaminants in the brake caliper mounting bracket surface and threads.

5. If any of the conditions listed are found, the disc brake pad mounting hardware requires replacement.

6. Ensure the disc brake pads are held firmly on the brake caliper mounting bracket, yet slide easily on the

mounting hardware without binding.

Fig. 12: Brake Caliper Mounting Bracket And Components Courtesy of GENERAL MOTORS COMPANY

7. Inspect the brake caliper mounting hardware for the following: Binding

Seizing

Looseness in the brake caliper mounting bracket (1) Bent or damaged brake caliper mounting bolts

Cracked or torn boots (4) Missing boots

Bent or damaged brake caliper mounting bracket (3) Cracked or damaged brake caliper (2)

8. If any of the conditions listed are found then the brake caliper mounting hardware requires replacement.

9. Install the disc brake pads to the caliper mounting bracket.

10. Install the disc brake caliper to the mounting bracket.

11. Install Rear Brake Caliper Bracket. Refer to Rear Brake Caliper Bracket Replacement

REPAIR INSTRUCTIONS

FRONT DISC BRAKE PADS REPLACEMENT

Removal Procedure

WARNING: Refer to Brake Dust Warning . WARNING: Refer to Brake Fluid Irritant Warning .

WARNING: Refer to Torque-to-Yield Fastener Warning . NOTE: Always replace disc brake pads in axle sets.

1. Inspect the fluid level in the brake master cylinder reservoir.

2. If the brake fluid level is midway between the maximum-full point and the minimum allowable level, no brake fluid needs to be removed before proceeding.

3. If the brake fluid level is higher than midway between the maximum-full point and the minimum allowable level, remove brake fluid to the midway point before proceeding.

4. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle

5. Remove the tire and wheel assembly. Refer to Tire and Wheel Removal and Installation

6. Place a large C-clamp over the brake caliper body and against the outer brake pad.

7. Using the C-clamp, carefully compress the brake caliper piston fully into the brake caliper bore.

Fig. 13: Brake Caliper Guide Pin Bolt Courtesy of GENERAL MOTORS COMPANY

NOTE: DO NOT use any air tools to remove or install the guide pin bolts. Use hand tools ONLY.

Install an open end wrench to hold the caliper guide pin in line with the

brake caliper while removing or installing caliper guide pin bolt. DO NOT allow the open end wrench to come in contact with the brake caliper.

Allowing the open end wrench to come in contact with the brake caliper will cause a pulsation when the brakes are applied.

8. Remove and DISCARD Brake Caliper Guide Pin Bolt (1)

Fig. 14: Front Brake Caliper

Courtesy of GENERAL MOTORS COMPANY

CAUTION: Support the brake caliper with heavy mechanic wire, or equivalent, whenever it is separated from its mount and the hydraulic flexible brake hose is still connected. Failure to support the caliper in this manner will cause the flexible brake hose to bear the weight of the caliper, which may cause damage to the brake hose and in turn may cause a brake fluid leak.

9. Remove Front Brake Caliper (1)

10. Pivot the brake caliper upward and secure with heavy mechanics wire, or equivalent.

Fig. 15: Front Brake Caliper Springs

Courtesy of GENERAL MOTORS COMPANY

11. Remove Front Brake Caliper Springs (1) (Qty: 2)

Fig. 16: Inner Disc Brake Pad

Courtesy of GENERAL MOTORS COMPANY

12. Remove Inner Disc Brake Pad (1)

Fig. 17: Outer Disc Brake Pad

Courtesy of GENERAL MOTORS COMPANY

13. Remove Outer Disc Brake Pad (1)

Fig. 18: Front Disc Brake Pad Retaining Springs Courtesy of GENERAL MOTORS COMPANY

14. Remove Front Disc Brake Pad Retaining Springs (1) (Qty: 2)

15. Thoroughly clean the disc brake pad retaining spring contact area and mating surfaces of the brake caliper bracket of any corrosion and debris.

16. Inspect the front brake caliper guide pins for freedom of movement and inspect the condition of the guide pin boots.

17. Move the brake caliper guide pins inboard and outboard within the brake caliper bracket guide pin bores, without disengaging the guide pins from the guide pin boots, and observe for the following conditions:

Restricted brake caliper guide pin movement

Looseness in the brake caliper bracket guide pin bores Seized or binding brake caliper guide pins

Split, torn, or otherwise damaged brake caliper guide pin boots

18. If any of the conditions listed are found, the brake caliper guide pins and/or brake caliper guide pin boots require replacement.

Installation Procedure

Fig. 19: Front Disc Brake Pad Retaining Springs Courtesy of GENERAL MOTORS COMPANY

1. Install Front Disc Brake Pad Retaining Springs (1) (Qty: 2)

Fig. 20: Outer Disc Brake Pad

Courtesy of GENERAL MOTORS COMPANY

2. Install Outer Disc Brake Pad (1)

Fig. 21: Inner Disc Brake Pad

Courtesy of GENERAL MOTORS COMPANY

NOTE: The inner disc brake pad must be positioned with the wear sensor at the disc brake pad leading edge.

3. Install Inner Disc Brake Pad (1)

Fig. 22: Front Brake Caliper Springs

Courtesy of GENERAL MOTORS COMPANY

4. Install Front Brake Caliper Springs (1) (Qty: 2)

Fig. 23: Front Brake Caliper

Courtesy of GENERAL MOTORS COMPANY

CAUTION: The phenolic brake caliper piston can be damaged if it contacts the edges of the brake pads upon installation. To avoid phenolic brake caliper piston damage, carefully hold the brake pads against the rotor and do NOT allow the caliper piston to contact the edges of the brake pads while installing the caliper. If the brake caliper piston sustains any damage, the entire caliper will need to be replaced.

5. Install Front Brake Caliper (1)

Fig. 24: Brake Caliper Guide Pin Bolt Courtesy of GENERAL MOTORS COMPANY

CAUTION: Refer to Fastener Caution . NOTE: Install a NEW bolt.

6. Install and tighten NEW Brake Caliper Guide Pin Bolt (1) to 40 N.m (30 lb ft)

7. Install the tire and wheel assembly. Refer to Tire and Wheel Removal and Installation

8. With the engine OFF, gradually apply the brake pedal to approximately 2/3 of its travel distance.

9. Slowly release the brake pedal.

10. Wait 15 seconds, then repeat steps 9-10 until a firm brake pedal is obtained. This will properly seat the brake caliper pistons and brake pads.

11. Fill the brake master cylinder reservoir to the maximum-full level with GM approved brake fluid from a clean, sealed brake fluid container. Refer to Master Cylinder Reservoir Filling

12. Burnish the brake pads and rotors. Refer to Brake Pad and Rotor Burnishing

REAR DISC BRAKE PADS REPLACEMENT

Removal Procedure

WARNING: Refer to Brake Dust Warning WARNING: Refer to Brake Fluid Irritant Warning

CAUTION: Refer to Brake Fluid Effects on Paint and Electrical Components Caution NOTE: Always replace disc brake pads in axle sets.

1. Inspect the fluid level in the brake master cylinder reservoir.

2. If the brake fluid level is midway between the maximum-full point and the minimum allowable level, no brake fluid needs to be removed before proceeding.

3. If the brake fluid level is higher than midway between the maximum-full point and the minimum allowable level, remove brake fluid to the midway point before proceeding.

4. Set the parking brake in service mode. With Scan Tool.

1. Connect the scan tool.

2. Ignition ON, engine OFF.

3. Select Electronic Brake Control Module.

4. Select Control Functions.

NOTE: Do not apply any brake pressure during the following step.

5. Select Rear Brake Caliper Piston Retract.

5. Turn OFF the ignition.

WARNING: Do not use a service jack in locations other than those specified to lift this vehicle. Lifting the vehicle with a jack in those other locations could cause the vehicle to slip off the jack and roll; this could cause injury or death.

6. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle

7. Remove the rear tire and wheel assemblies. Refer to Tire and Wheel Removal and Installation

Fig. 25: Brake Caliper And Electrical Connector Courtesy of GENERAL MOTORS COMPANY

8. Disconnect Electrical Connector (1)

9. Remove Wiring Harness @ Brake Caliper (2)

Fig. 26: Brake Caliper And Guide Pin Bolt Courtesy of GENERAL MOTORS COMPANY

NOTE: Do NOT disconnect the brake hoses from the calipers.

NOTE: Do NOT use any air tools to remove or install the brake caliper guide pin bolts. Use hand tools ONLY.

Install an open end wrench to hold the caliper guide pin in line with the brake caliper while removing or installing the caliper guide pin bolt.

Allowing the open end wrench to come in contact with the brake caliper will cause a pulsation when the brakes are applied.

10. Remove and DISCARD Brake Caliper Guide Pin Bolt (2)

Fig. 27: Rear Brake Caliper And Rear Disc Brake Pads Courtesy of GENERAL MOTORS COMPANY

brake hose to bear the weight of the caliper, which may cause damage to the brake hose and in turn may cause a brake fluid leak.

11. Without disconnecting the hydraulic brake flexible hose, pivot the rear brake caliper (2) downward and secure with heavy mechanics wire, or equivalent.

12. Remove Rear Disc Brake Pads (1) (Qty: 2)

Fig. 28: Rear Brake Caliper Bracket And Brake Pad Springs Courtesy of GENERAL MOTORS COMPANY

NOTE: If installing NEW brake pads, DISCARD the springs.

13. Remove Brake Pad Springs (2) (Qty: 2) @ Brake Caliper Bracket (1)

14. Thoroughly clean the brake pad hardware mating surfaces of the caliper bracket of any debris and corrosion.

15. Inspect the rear brake caliper guide pins for freedom of movement and inspect the condition of the guide pin boots. Move the guide pins inboard and outboard within the bracket bores, without disengaging the slides from the boots, and observe for the following:

Restricted caliper guide pin movement

Looseness in the brake caliper mounting bracket Seized or binding caliper guide pins

Split or torn boots.

16. If any of the conditions listed are found, the brake caliper guide pins and/or boots require replacement.

Installation Procedure

Fig. 29: Rear Brake Caliper Bracket And Brake Pad Springs Courtesy of GENERAL MOTORS COMPANY

1. Ensure the brake pad hardware mating surfaces are clean.

NOTE: If installing new brake pads, install new brake pad springs.

2. Install Brake Pad Springs (2) (Qty: 2) @ Brake Caliper Bracket (1)

Fig. 30: Inner Brake Pad Nose And Piston Slot Courtesy of GENERAL MOTORS COMPANY

3. Ensure the brake caliper piston slots are aligned vertically and the inner brake pad nose (2) fits into the piston slot (1).

Fig. 31: Rear Brake Caliper And Rear Disc Brake Pads Courtesy of GENERAL MOTORS COMPANY

NOTE: The disc brake pad equipped with wear sensor has to be mounted in lower position on the inner side of the rotor.

4. Install Rear Disc Brake Pads (1) (Qty: 2) @ Rear Brake Caliper Bracket

NOTE: Do not rotate the brake caliper piston.

5. Push the brake caliper piston into the brake caliper housing. Use a suitable tool.

Fig. 32: Brake Caliper And Guide Pin Bolt Courtesy of GENERAL MOTORS COMPANY

6. Remove the support, and rotate the rear brake caliper (1) into position over the disc brake pads and to the caliper mounting bracket.

WARNING: Refer to Torque-to-Yield Fastener Warning CAUTION: Refer to Fastener Caution

NOTE: Install an open end wrench to hold the caliper guide pin in line with the brake caliper while removing or installing the caliper guide pin bolt.

7. Install the NEW upper rear brake caliper guide pin bolt (2) and tighten to 36 N.m (27 lb ft). Counter the hex flange on the rear brake caliper bracket using a suitable wrench.

Fig. 33: Brake Caliper And Electrical Connector Courtesy of GENERAL MOTORS COMPANY

8. Install Wiring Harness @ Brake Caliper (2)

9. Connect Electrical Connector (1)

10. Install the rear tire and wheel assemblies. Refer to Tire and Wheel Removal and Installation

11. With the engine OFF, gradually apply the brake pedal to approximately 2/3 of its travel distance.

12. Slowly release the brake pedal.

13. Wait 15 seconds, then gradually apply the brake pedal approximately 2/3 of its travel distance again until a firm brake pedal apply is obtained. This will properly seat the brake caliper pistons and brake pads.

14. Inspect the fluid level in the brake master cylinder reservoir.

15. Fill the brake master cylinder reservoir to the maximum-full level with GM approved brake fluid from a clean, sealed brake fluid container. Refer to Master Cylinder Reservoir Filling

16. Perform Parking Brake Calibration. Refer to Park Brake Calibration

17. Burnish the brake pads and rotors. Refer to Brake Pad and Rotor Burnishing

BRAKE PAD AND ROTOR BURNISHING

WARNING: Road test a vehicle under safe conditions and while obeying all traffic laws. Do not attempt any maneuvers that could jeopardize vehicle control. Failure to adhere to these precautions could lead to serious personal injury and vehicle damage.

Burnishing the brake pads and brake rotors is necessary in order to ensure that the braking surfaces are properly prepared after service has been performed on the disc brake system.

This procedure should be performed whenever the disc brake rotors have been refinished or replaced, and/or whenever the disc brake pads have been replaced.

1. Select a smooth road with little or no traffic.

2. Accelerate the vehicle to 48 km/h (30 mph).

NOTE: Use care to avoid overheating the brakes while performing this step.

3. Using moderate to firm pressure, apply the brakes to bring the vehicle to a stop. Do not allow the brakes to lock.

4. Repeat steps 2 and 3 until approximately 20 stops have been completed. Allow sufficient cooling periods between stops in order to properly burnish the brake pads and rotors.

FRONT BRAKE CALIPER REPLACEMENT

Removal Procedure

WARNING: Refer to Brake Dust Warning WARNING: Refer to Brake Fluid Irritant Warning

WARNING: Use of eye goggles is necessary to prevent personal injury.

CAUTION: Refer to Brake Fluid Effects on Paint and Electrical Components Caution

1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .

2. Remove the front tire and wheel assemblies. Refer to Tire and Wheel Removal and Installation .

Fig. 34: Brake Hose Fitting Bolt, Sealing Washers And Front Brake Caliper Courtesy of GENERAL MOTORS COMPANY

3. Remove Brake Hose Fitting Bolt (1) @ Front Brake Caliper (3)

4. Remove Brake Hose @ Front Brake Caliper (3)

5. Cap the opening in the brake caliper and the brake hose to prevent fluid loss and contamination.

6. Remove and DISCARD Sealing Washer (2) @ Front Brake Caliper

7. Remove and DISCARD Sealing Washer (2) @ Brake Hose

Fig. 35: Brake Caliper Guide Pin Bolts And Front Brake Caliper Courtesy of GENERAL MOTORS COMPANY

8. Remove Brake Caliper Guide Pin Bolts (1) (Qty: 2) @ Front Brake Caliper (2)

9. Remove Front Brake Caliper (2)

Fig. 36: Brake Caliper Guide Pins, Boots And Caliper Mounting Bracket Courtesy of GENERAL MOTORS COMPANY

10. Inspect the brake caliper guide pins (1) for freedom of movement, and inspect the condition of the guide pin boots (2). Move the guide pins inboard and outboard within the bracket bores, without disengaging the slides from the boots, and observe for the following:

Restricted caliper guide pin movement

Looseness in the brake caliper mounting bracket Seized or binding caliper guide pins

Split or torn boots

11. If a condition exists - Replace damaged components.

Installation Procedure

Fig. 37: Brake Caliper Guide Pin Bolts And Front Brake Caliper Courtesy of GENERAL MOTORS COMPANY

1. Install Front Brake Caliper (2)

CAUTION: Fastener Caution

2. Install and tighten Brake Caliper Guide Pin Bolts (1) (Qty: 2) @ Front Brake Caliper (2) to 40 N.m (30 lb ft)

Fig. 38: Brake Hose Fitting Bolt, Sealing Washers And Front Brake Caliper Courtesy of GENERAL MOTORS COMPANY

3. Install NEW Sealing Washers (2) (Qty: 2) Install a NEW seal.

4. Remove the caps from the brake caliper opening and the brake hose.

5. Install Brake Hose @ Front Brake Caliper (3)

6. Install and tighten Brake Hose Fitting Bolt (1) @ Front Brake Caliper (3) to 40 N.m (30 lb ft)

7. Bleed the brake system. Refer to Hydraulic Brake System Bleeding

8. Install the front tire and wheel assemblies. Refer to Tire and Wheel Removal and Installation .

9. Remove the support and lower the vehicle.

10. With the engine OFF, gradually apply the brake pedal to approximately 2/3 of its travel distance.

11. Slowly release the brake pedal.

12. Wait 15 seconds, then repeat step 11 and 12 until a firm brake pedal is obtained.

REAR BRAKE CALIPER REPLACEMENT

Removal Procedure

WARNING: Refer to Brake Dust Warning

WARNING: Refer to Brake Fluid Irritant Warning

WARNING: Use of eye goggles is necessary to prevent personal injury.

CAUTION: Refer to Brake Fluid Effects on Paint and Electrical Components Caution

1. Set the parking brake in service mode.

1. Connect the scan tool.

2. Ignition ON, engine OFF.

3. Select "Electronic Brake Control Module".

4. Select "Control Functions".

NOTE: Do not apply any brake pressure during the following step.

5. Select "Rear Brake Caliper Piston Retract".

2. Turn OFF the ignition.

3. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle

4. Remove the rear tire and wheel assemblies. Refer to Tire and Wheel Removal and Installation

Fig. 39: Brake Hose, Fitting Bolt And Sealing Washers Courtesy of GENERAL MOTORS COMPANY

5. Remove Brake Hose Fitting Bolt (1) @ Rear Brake Caliper

6. Remove Brake Hose (2) @ Rear Brake Caliper

7. Cap the brake hose fitting to prevent brake fluid loss and contamination.

8. DISCARD the brake hose fitting gaskets. (3) (Qty: 2)

Fig. 40: Brake Caliper And Electrical Connector Courtesy of GENERAL MOTORS COMPANY

9. Disconnect the electrical connector (1) and remove the wiring harness from the brake caliper assembly (2).

Fig. 41: Rear Brake Caliper And Guide Pin Bolts Courtesy of GENERAL MOTORS COMPANY

10. Remove Brake Caliper Guide Pin Bolts (2) (Qty: 2) @ Rear Brake Caliper (1)

11. Remove Rear Brake Caliper

Fig. 42: Brake Caliper Guide Pins, Boots And Caliper Mounting Bracket Courtesy of GENERAL MOTORS COMPANY

12. Inspect the brake caliper guide pins (3) for freedom of movement, and inspect the condition of the guide pin boots (2). Move the guide pins inboard and outboard within the bracket bores, without disengaging the slides from the boots, and observe for the following:

Restricted caliper guide pin movement

Looseness in the brake caliper mounting bracket Seized or binding caliper guide pins

Split or torn boots

13. If a condition exists - Replace damaged components.

14. Remove Rear Parking Brake Actuator. Refer to Rear Parking Brake Actuator Replacement

Installation Procedure

1. Install Rear Parking Brake Actuator. Refer to Rear Parking Brake Actuator Replacement

Fig. 43: Rear Brake Caliper And Guide Pin Bolts Courtesy of GENERAL MOTORS COMPANY

2. Install Rear Brake Caliper (1)

CAUTION: Refer to Fastener Caution

NOTE: Do not rotate the brake caliper piston.

3. Install and tighten Brake Caliper Guide Pin Bolts (2) (Qty: 2) @ Rear Brake Caliper to 36 N.m (27 lb ft)

Fig. 44: Brake Caliper And Electrical Connector Courtesy of GENERAL MOTORS COMPANY

4. Connect the electrical connector (1) and fix the wiring harness with 2 cable straps to the brake caliper assembly (2).

5. Remove the caps from the brake caliper opening and the brake hose.

Fig. 45: Brake Hose, Fitting Bolt And Sealing Washers Courtesy of GENERAL MOTORS COMPANY

6. Install NEW brake hose fitting gaskets. (3) (Qty: 2)

7. Install and tighten Brake Hose Fitting Bolt (1) @ Rear Brake Caliper to 40 N.m (30 lb ft)

8. Bleed the brake system. Refer to Hydraulic Brake System Bleeding

9. Install the rear tire and wheel assemblies. Refer to Tire and Wheel Removal and Installation .

10. Remove the support and lower the vehicle.

11. With the engine OFF, gradually apply the brake pedal to approximately 2/3 of its travel distance.

12. Slowly release the brake pedal.

13. Wait 15 seconds, then repeat step 10 and 11 until a firm brake pedal is obtained.

14. Calibrate the park brake. Refer to Park Brake Calibration .

REAR BRAKE CALIPER GUIDE PIN REPLACEMENT

Removal Procedure

1. Remove the rear tire and wheel assemblies. Refer to Tire and Wheel Removal and Installation

Fig. 46: Brake Caliper And Guide Pin Bolts Courtesy of GENERAL MOTORS COMPANY

NOTE: Do NOT disconnect the brake hoses from the calipers.

2. Remove Brake Caliper Guide Pin Bolts (2) (Qty: 2) @ Rear Brake Caliper (1)

3. Remove the brake caliper assembly and support with heavy mechanics wire.

Fig. 47: Brake Caliper Guide Pins, Boots And Caliper Mounting Bracket Courtesy of GENERAL MOTORS COMPANY

4. Remove Rear Brake Caliper Guide Pins (3) (Qty: 2)

Installation Procedure

Fig. 48: Brake Caliper Guide Pins, Boots And Caliper Mounting Bracket Courtesy of GENERAL MOTORS COMPANY

1. Apply a light coating of high temperature, silicone brake lubricant to the brake caliper bracket guide pin bores, the inner portion of the guide pin seals, and the brake caliper guide pins. Refer to Adhesives, Fluids, Lubricants, and Sealers

2. Install Rear Brake Caliper Guide Pins (3) (Qty: 2)

3. Inspect the brake caliper guide pins (3) for free movement, and inspect the condition of the guide pin boots (2). Move the guide pins inboard and outboard within the bracket bores, without disengaging the slides from the boots, and observe for the following:

Restricted caliper guide pin movement

Looseness in the brake caliper mounting bracket Seized or binding caliper guide pins

Split or torn boots

Fig. 49: Brake Caliper And Guide Pin Bolts Courtesy of GENERAL MOTORS COMPANY

CAUTION: Refer to Fastener Caution

4. Install and tighten Brake Caliper Guide Pin Bolts (2) (Qty: 2) @ Front Brake Caliper (1) to 36 N.m (27 lb ft)

5. Install the rear tire and wheel assemblies. Refer to Tire and Wheel Removal and Installation

FRONT BRAKE CALIPER OVERHAUL

Disassembly Procedure

WARNING: Refer to Brake Dust Warning . WARNING: Refer to Brake Fluid Irritant Warning .

WARNING: Use of eye goggles is necessary to prevent personal injury.

WARNING: Do not place fingers in front of the caliper piston(s) in an attempt to catch or protect it when applying compressed air. The piston(s) can fly out with force and could result in serious bodily injury.

CAUTION: Use clean cloths to pad interior of caliper housing during piston removal. Use just enough air to ease the pistons out of the bores. If the pistons are blown out, even with the padding provided, it may be damaged.

1. Remove the brake caliper from the vehicle. Refer to Front Brake Caliper Replacement.

Fig. 50: Using Low Pressure Compressed Air To Remove Brake Caliper Piston Courtesy of GENERAL MOTORS COMPANY

Fig. 51: Exploded View Of Brake Caliper Courtesy of GENERAL MOTORS COMPANY

2. Remove the brake caliper piston from the caliper bore by directing low pressure compressed air into the caliper

(1) through the fluid inlet hole.

3. Remove the piston dust boot seal (1) from the seal counterbore in the caliper (4). Discard the boot seal.

4. Using a small wooden or plastic tool, remove the piston seal (3) from the caliper bore. Discard the piston seal.

5. Remove the bleeder valve cap (6).

6. Remove the bleeder valve (5).

NOTE: Do not use abrasives to clean the brake caliper piston.

7. If cracks, scoring, pitting, excessive rust, and/or excessive corrosion are present in the caliper bore, replace the caliper assembly.

8. If light rust or light corrosion are present in the caliper bore, attempt to remove the imperfection with a fine emery paper. If the imperfection cannot be removed, replace the caliper assembly.

9. Clean the brake caliper piston bore and seal counterbore, and the caliper piston with denatured alcohol, or equivalent.

10. Dry the caliper piston bore and counterbore, and the piston with non-lubricated, filtered, compressed air.

11. Inspect the caliper piston for cracks, scoring, and/or damage to the plating. Replace the caliper piston if any of these conditions exist.

12. Inspect the caliper mounting holes for cracks, scoring, pitting, rust and/or excessive corrosion. Replace the caliper assembly if any of these conditions exist.

Assembly Procedure

Fig. 52: Exploded View Of Brake Caliper Courtesy of GENERAL MOTORS COMPANY

1. Lubricate the new piston seal (3) with brake fluid from a clean, sealed brake fluid container. Refer to

Adhesives, Fluids, Lubricants, and Sealers for the recommended brake fluid.

2. Install the lubricated, new piston seal into the caliper bore.

CAUTION: Refer to Fastener Caution .

3. Install the bleeder valve (5) to the caliper and tighten the valve to 10 N.m (88.508 lb in).

4. Install the bleeder valve cap (6).

5. Apply a thin coat of brake fluid from a clean, sealed brake fluid container to the brake caliper (4) bore. Refer to Adhesives, Fluids, Lubricants, and Sealers for the recommended brake fluid.

Fig. 53: Caliper Piston And Caliper Piston Dust Boot Seal Courtesy of GENERAL MOTORS COMPANY

6. Install the new piston dust boot seal (1) over the caliper piston.

7. Install the bottom half of the caliper piston (2) into the caliper bore.

8. Compress the caliper piston to the bottom of the caliper bore.

9. Fully seat the piston dust boot seal into caliper counterbore.

10. Install the brake caliper to the vehicle. Refer to Front Brake Caliper Replacement.

REAR BRAKE CALIPER MOUNT PLATE REPLACEMENT

Special Tools

EN-45059 Angle Meter

Equivalent regional tools: Special Tools

Removal Procedure

1. Remove the rear tire and wheel assemblies. Refer to Tire and Wheel Removal and Installation

2. Remove Rear Brake Rotor. Refer to Rear Brake Rotor Replacement

3. Remove Rear Wheel Speed Sensor. Refer to Rear Wheel Speed Sensor Replacement

Fig. 54: Rear Shock Absorber, Bolt And Hydraulic Lift Courtesy of GENERAL MOTORS COMPANY

4. Support the rear axle with a hydraulic lift table. (3)

5. Remove Rear Shock Absorber Bolt (2)

6. Push up to the shock absorber (1) gain access to the rear wheel bearing and hub bolts.

Fig. 55: Rear Wheel Bearing And Hub Bolts Courtesy of GENERAL MOTORS COMPANY

7. Remove Bolts (1) (Qty: 4)

Fig. 56: Rear Brake Caliper Mount Plate, Rear Brake Shield, Rear Wheel Bearing and Hub Assembly Courtesy of GENERAL MOTORS COMPANY

8. Remove Rear Wheel Bearing and Hub Assembly (1)

9. Remove the rear brake shield (2).

10. Remove the rear brake caliper mount plate (3).

Installation Procedure

Fig. 57: Rear Brake Caliper Mount Plate, Rear Brake Shield, Rear Wheel Bearing and Hub Assembly Courtesy of GENERAL MOTORS COMPANY

1. Install the rear brake caliper mount plate (3).

2. Install the rear brake shield (2).

3. Install Rear Wheel Bearing and Hub Assembly (1)

Fig. 58: Rear Wheel Bearing And Hub Bolts Courtesy of GENERAL MOTORS COMPANY

CAUTION: Refer to Fastener Caution

4. Apply thread locking adhesive to the fasteners.

5. Install and tighten Bolts (1) (Qty: 4)

1. First Pass: 50 N.m (37 lb ft).

2. Final Pass: 30 - 45 degrees, use the EN-45059 meter

Fig. 59: Rear Shock Absorber, Bolt And Hydraulic Lift Courtesy of GENERAL MOTORS COMPANY

NOTE: Service may offer bolts without micro-encapsulated thread locking adhesive. If this is the case, apply thread locking adhesive to the bolt.

6. Support the rear axle with a tall jack stand near the shock absorber.

7. Install, but do NOT tighten Rear Shock Absorber Bolt (2)

8. Install Rear Wheel Speed Sensor. Refer to Rear Wheel Speed Sensor Replacement

9. Install Rear Brake Rotor. Refer to Rear Brake Rotor Replacement

10. Install Tire and Wheel. Refer to Tire and Wheel Removal and Installation

11. Lower the vehicle.

Fig. 60: Rear Shock Absorber Bolt

Courtesy of GENERAL MOTORS COMPANY

NOTE: Tighten the bolt with vehicle standing on the ground.

12. Tighten Rear Shock Absorber Bolt (1) to 100 N.m (74 lb ft)

FRONT BRAKE CALIPER HARDWARE REPLACEMENT

Removal Procedure

WARNING: Refer to Brake Dust Warning

1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle

2. Remove the front tire and wheel assemblies. Refer to Tire and Wheel Removal and Installation

Fig. 61: Front Brake Caliper And Guide Pin Bolts Courtesy of GENERAL MOTORS COMPANY

NOTE: Do NOT disconnect the brake hoses from the calipers.

NOTE: Do NOT use any air tools to remove or install the brake caliper guide pin bolts. Use hand tools ONLY.

Install an open end wrench to hold the caliper guide pin in line with the brake caliper while removing or installing the caliper guide pin bolt.

Allowing the open end wrench to come in contact with the brake caliper will cause a pulsation when the brakes are applied.

3. Remove and DISCARD Brake Caliper Guide Pin Bolts (1) (Qty: 2) @ Front Brake Caliper (2)

4. Remove Front Brake Caliper (2)

Fig. 62: Disc Brake Pads

Courtesy of GENERAL MOTORS COMPANY

5. Remove the disc brake pads. (1) (Qty: 2)

Fig. 63: Brake Caliper Guide Pins, Boots And Caliper Mounting Bracket Courtesy of GENERAL MOTORS COMPANY

NOTE: The lower brake caliper guide pin is equipped with a bushing and must be installed in the same location.

6. Remove Front Brake Caliper Guide Pins (1) (Qty: 2) @ Front Brake Caliper Bracket (3)

Fig. 64: Brake Pad Springs And Caliper Bracket Courtesy of GENERAL MOTORS COMPANY

7. Remove Brake Pad Springs (2) (Qty: 2) @ Brake Caliper Bracket (1)

Installation Procedure

Fig. 65: Brake Pad Springs And Caliper Bracket Courtesy of GENERAL MOTORS COMPANY

1. Install Brake Pad Springs (2) (Qty: 2) @ Brake Caliper Bracket (1)

Fig. 66: Brake Caliper Guide Pins, Boots And Caliper Mounting Bracket Courtesy of GENERAL MOTORS COMPANY

2. Seat the brake caliper guide pin seal in the groove of the brake caliper guide pin. (2)

NOTE: The lower brake caliper guide pin is equipped with a bushing and must be installed in the same location.

3. Install Front Brake Caliper Guide Pins (1) (Qty: 2) @ Front Brake Caliper Bracket (3)

4. Inspect the brake caliper guide pins (1) for freedom of movement, and inspect the condition of the guide pin boots (2). Move the guide pins inboard and outboard within the bracket bores, without disengaging the slides from the boots, and observe for the following:

Restricted caliper guide pin movement

Looseness in the brake caliper mounting bracket Seized or binding caliper guide pins

Split or torn boots

5. Ensure the brake caliper guide pin seal is fully seated in the groove of the brake caliper guide pin and the guide pin slides freely in caliper bracket bore.

Fig. 67: Disc Brake Pads

Courtesy of GENERAL MOTORS COMPANY

6. Install the disc brake pads. (1) (Qty: 2)

Fig. 68: Rear Brake Caliper

Courtesy of GENERAL MOTORS COMPANY

7. Install Front Brake Caliper (2)

WARNING: Refer to Torque-to-Yield Fastener Warning CAUTION: Refer to Fastener Caution

NOTE: Install an open end wrench to hold the caliper guide pin in line with the brake caliper while removing or installing the caliper guide pin bolt.

8. Install NEW Brake Caliper Guide Pin Bolts (1) (Qty: 2) @ Front Brake Caliper (2) and tighten to 40 N.m (30 lb ft). Install NEW bolts.

9. Install Tire and Wheel. Refer to Tire and Wheel Removal and Installation

REAR BRAKE CALIPER HARDWARE REPLACEMENT

Removal Procedure

WARNING: Do not use a service jack in locations other than those specified to lift this vehicle.

Lifting the vehicle with a jack in those other locations could cause the vehicle to slip off the jack and roll; this could cause injury or death.

WARNING: Refer to Brake Dust Warning WARNING: Refer to Brake Fluid Irritant Warning

1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle

2. Remove the tire and wheel assembly. Refer to Tire and Wheel Removal and Installation

Fig. 69: Brake Caliper And Guide Pin Bolts Courtesy of GENERAL MOTORS COMPANY

NOTE: Do NOT disconnect the brake hoses from the calipers.

NOTE: Do NOT use any air tools to remove or install the brake caliper guide pin bolts. Use hand tools ONLY.

Install an open end wrench to hold the caliper guide pin in line with the brake caliper while removing or installing the caliper guide pin bolt.

Allowing the open end wrench to come in contact with the brake caliper will cause a pulsation when the brakes are applied.

3. Remove and DISCARD Brake Caliper Guide Pin Bolts (2) (Qty: 2) @ Rear Brake Caliper (1)

4. Remove the brake caliper assembly and support with heavy mechanics wire.

Fig. 70: Disc Brake Pads

Courtesy of GENERAL MOTORS COMPANY

5. Remove the disc brake pads. (1) (Qty: 2)

Fig. 71: Brake Caliper Bracket And Brake Pad Springs Courtesy of GENERAL MOTORS COMPANY

6. Remove Brake Pad Springs (1) (Qty: 2) @ Brake Caliper Bracket (2)

Fig. 72: Brake Caliper Guide Pins, Boots And Caliper Mounting Bracket Courtesy of GENERAL MOTORS COMPANY

7. Seat the brake caliper guide pin seal in the groove of the brake caliper guide pin. (2) (Qty: 2)

NOTE: The lower brake caliper guide pin is equipped with a bushing and must be installed in the same location.

8. Install Rear Brake Caliper Guide Pins (3) (Qty: 2)

NOTE: If reusing the brake caliper guide pins (3) and the guide pin seals (2).

Inspect the brake caliper guide pins for freedom of movement, and inspect the condition of the guide pin boots. Move the guide pins inboard and outboard within the bracket bores, without disengaging the slides from the boots, and observe for the following:

Restricted caliper guide pin movement

Looseness in the brake caliper mounting bracket Seized or binding caliper guide pins

Split or torn boots

9. Ensure the brake caliper guide pin seal is fully seated in the groove of the brake caliper guide pin and the guide pin slides freely in caliper bracket bore.

Installation Procedure

Fig. 73: Brake Caliper Bracket And Brake Pad Springs Courtesy of GENERAL MOTORS COMPANY

1. Install Brake Pad Springs (1) (Qty: 2) @ Brake Caliper Bracket (2)

Fig. 74: Disc Brake Pads

Courtesy of GENERAL MOTORS COMPANY

NOTE: The disc brake pad equipped with wear sensor has to be mounted in lower position on the inner side of the rotor.

2. Install the disc brake pads. (1) (Qty: 2)

Fig. 75: Brake Caliper And Guide Pin Bolts Courtesy of GENERAL MOTORS COMPANY

3. Install the brake caliper. (1)

WARNING: Refer to Torque-to-Yield Fastener Warning CAUTION: Refer to Fastener Caution

NOTE: Install an open end wrench to hold the caliper guide pin in line with the brake caliper while removing or installing the caliper guide pin bolt.

4. Install NEW Brake Caliper Guide Pin Bolts (2) (Qty: 2) @ Rear Brake Caliper (1) and tighten to 36 N.m (27 lb ft). Install NEW bolts.

5. Install the tire and wheel assembly. Refer to Tire and Wheel Removal and Installation

6. Remove the support and lower the vehicle.

7. With the engine OFF, gradually apply the brake pedal to approximately 2/3 of its travel distance.

8. Slowly release the brake pedal.

9. Wait 15 seconds, then gradually apply the brake pedal approximately 2/3 of its travel distance again until a firm brake pedal apply is obtained. This will properly seat the brake caliper pistons and brake pads.

10. Inspect the fluid level in the brake master cylinder reservoir.

11. Fill the brake master cylinder reservoir to the maximum-full level with GM approved brake fluid from a clean, sealed brake fluid container. Refer to Master Cylinder Reservoir Filling

FRONT BRAKE CALIPER BRACKET REPLACEMENT

Special Tools

EN-45059 Angle Meter

Equivalent regional tools: Special Tools

Removal Procedure

WARNING: Do not use a service jack in locations other than those specified to lift this

vehicle. Lifting the vehicle with a jack in those other locations could cause the vehicle to slip off the jack and roll; this could cause injury or death.

WARNING: Refer to Brake Dust Warning .

1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle

2. Remove the front tire and wheel assemblies. Refer to Tire and Wheel Removal and Installation

Fig. 76: Front Brake Caliper And Guide Pin Bolts Courtesy of GENERAL MOTORS COMPANY

NOTE: Do NOT disconnect the brake hoses from the calipers.

NOTE: Do NOT use any air tools to remove or install the brake caliper guide pin bolts. Use hand tools ONLY.

Install an open end wrench to hold the caliper guide pin in line with the brake caliper while removing or installing the caliper guide pin bolt.

Allowing the open end wrench to come in contact with the brake caliper will cause a pulsation when the brakes are applied.

3. Remove and DISCARD Brake Caliper Guide Pin Bolts (1) (Qty: 2) @ Front Brake Caliper (2)

4. Remove Front Brake Caliper

Fig. 77: Disc Brake Pads

Courtesy of GENERAL MOTORS COMPANY

5. Remove the disc brake pads. (1) (Qty: 2)

Fig. 78: Brake Pad Springs And Caliper Bracket Courtesy of GENERAL MOTORS COMPANY

6. Remove Brake Pad Springs (2) (Qty: 2) @ Brake Caliper Bracket (1)

Fig. 79: Brake Caliper Bracket And Bolts Courtesy of GENERAL MOTORS COMPANY

7. Remove Bolts (1) (Qty: 2) @ Brake Caliper Bracket (2)

8. Remove Front Brake Caliper Bracket

Installation Procedure

Fig. 80: Brake Caliper Bracket And Bolts Courtesy of GENERAL MOTORS COMPANY

1. Install Front Brake Caliper Bracket (2)

CAUTION: Refer to Fastener Caution

2. Install and tighten Bolts (1) (Qty: 2) @ Brake Caliper Bracket (2)

1. First Pass: 150 N.m (111 lb ft).

2. Final Pass: 15 - 30 degrees

Fig. 81: Brake Caliper Guide Pins, Boots And Caliper Mounting Bracket Courtesy of GENERAL MOTORS COMPANY

3. Apply a light coating of high temperature, silicone brake lubricant to the brake caliper bracket guide pin bores, the inner portion of the guide pin seals, and the brake caliper guide pins.

4. Seat the brake caliper guide pin seal in the groove of the brake caliper guide pin. (2) (Qty: 2)

NOTE: The lower brake caliper guide pin is equipped with a bushing and must be installed in the same location.

5. Install Front Brake Caliper Guide Pins (1) (Qty: 2)

6. Ensure the brake caliper guide pin seal is fully seated in the groove of the brake caliper guide pin and the guide pin slides freely in caliper bracket bore.

NOTE: If reusing the brake caliper guide pins (1) and the guide pin seals (2).

Restricted caliper guide pin movement

Looseness in the brake caliper mounting bracket Seized or binding caliper guide pins

Split or torn boots

Fig. 82: Brake Pad Springs And Caliper Bracket Courtesy of GENERAL MOTORS COMPANY

7. Install Brake Pad Springs (2) (Qty: 2) @ Brake Caliper Bracket (1)

Fig. 83: Disc Brake Pads

Courtesy of GENERAL MOTORS COMPANY

NOTE: The disc brake pad equipped with wear sensor has to be mounted in upper position on the inner side of the rotor.

8. Install the disc brake pads. (1) (Qty: 2)

Fig. 84: Front Brake Caliper And Guide Pin Bolts Courtesy of GENERAL MOTORS COMPANY

9. Install the brake caliper. (2)

WARNING: Refer to Torque-to-Yield Fastener Warning

NOTE: Install an open end wrench to hold the caliper guide pin in line with the brake caliper while removing or installing the caliper guide pin bolt.

10. Install and tighten Brake Caliper Guide Pin Bolts (1) (Qty: 2) @ Front Brake Caliper (2) to 40 N.m (30 lb ft)

11. Install the front tire and wheel assemblies. Refer to Tire and Wheel Removal and Installation

12. With the engine OFF, gradually apply the brake pedal to approximately 2/3 of its travel distance.

13. Slowly release the brake pedal.

14. Wait 15 seconds, then gradually apply the brake pedal approximately 2/3 of its travel distance again until a firm brake pedal apply is obtained. This will properly seat the brake caliper pistons and brake pads.

15. Inspect the fluid level in the brake master cylinder reservoir.

16. Fill the brake master cylinder reservoir to the maximum-full level with GM approved brake fluid from a clean, sealed brake fluid container. Refer to Master Cylinder Reservoir Filling

REAR BRAKE CALIPER BRACKET REPLACEMENT

Special Tools

EN-45059 Angle Meter

Equivalent regional tools: Special Tools

Removal Procedure

WARNING: Refer to Brake Dust Warning

1. Set the parking brake in service mode

1. Change the transmission gear in neutral position.

2. Press the electronic park brake switch until the red parking brake status lamp is illuminating in the instrument cluster.

NOTE: Do not press the brake pedal intensely. It is sufficient when the brake lights are illuminated.

3. Press the brake pedal 5 times slightly until the vacuum in the power brake booster is empty.

4. Turn the ignition ON, with the engine OFF.

5. Press the brake pedal slightly and the electronic park brake switch for 15 seconds until the orange brake service lamp is illuminating.

6. By keeping brake pedal applied, release and re-press the electronic park brake switch for 5 seconds.

7. Release the electronic park brake switch and the brake pedal simultaneously. The rear brake calipers are retracting and the orange service brake lamp is flashing.

2. Turn OFF the ignition.

3. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle

4. Remove the front tire and wheel assemblies. Refer to Tire and Wheel Removal and Installation

Fig. 85: Brake Caliper And Guide Pin Bolts Courtesy of GENERAL MOTORS COMPANY

NOTE: Do NOT disconnect the brake hoses from the calipers.

NOTE: Do NOT use any air tools to remove or install the brake caliper guide pin bolts. Use hand tools ONLY.

Install an open end wrench to hold the caliper guide pin in line with the brake caliper while removing or installing the caliper guide pin bolt.

Allowing the open end wrench to come in contact with the brake caliper will cause a pulsation when the brakes are applied.

5. Remove and DISCARD Brake Caliper Guide Pin Bolts (2) (Qty: 2) @ Rear Brake Caliper (1)

6. Remove the brake caliper assembly.

Fig. 86: Disc Brake Pads

Courtesy of GENERAL MOTORS COMPANY

7. Remove the disc brake pads. (1) (Qty: 2)

Fig. 87: Brake Caliper Bracket And Brake Pad Springs Courtesy of GENERAL MOTORS COMPANY

8. Remove Brake Pad Springs (1) (Qty: 2) @ Brake Caliper Bracket (2)

Fig. 88: Rear Brake Caliper Bracket And Bolts Courtesy of GENERAL MOTORS COMPANY

9. Remove Bolts (2) (Qty: 2) @ Rear Brake Caliper Bracket (1)

10. Remove Rear Brake Caliper Bracket

Installation Procedure

Fig. 89: Rear Brake Caliper Bracket And Bolts Courtesy of GENERAL MOTORS COMPANY

1. Install Rear Brake Caliper Bracket (1)

CAUTION: Refer to Fastener Caution

2. Install and tighten Bolts (2) (Qty: 2) @ Brake Caliper Bracket

1. First Pass: 100 N.m (74 lb ft).

2. Final Pass: 15 - 30 degrees, using the EN-45059 meter

Fig. 90: Brake Caliper Guide Pins, Boots And Caliper Mounting Bracket Courtesy of GENERAL MOTORS COMPANY

3. Apply a light coating of high temperature, silicone brake lubricant to the brake caliper bracket guide pin bores, the inner portion of the guide pin seals, and the brake caliper guide pins.

4. Seat the brake caliper guide pin seal in the groove of the brake caliper guide pin. (2) (Qty: 2)

NOTE: The lower brake caliper guide pin is equipped with a bushing and must be installed in the same location.

5. Install Front Brake Caliper Guide Pins (1) (Qty: 2)

6. Ensure the brake caliper guide pin seal is fully seated in the groove of the brake caliper guide pin and the guide pin slides freely in caliper bracket bore.

NOTE: If reusing the brake caliper guide pins (3) and the guide pin seals (2).

Restricted caliper guide pin movement

Looseness in the brake caliper mounting bracket Seized or binding caliper guide pins

Split or torn boots

Fig. 91: Brake Caliper Bracket And Brake Pad Springs Courtesy of GENERAL MOTORS COMPANY

7. Install Brake Pad Springs (1) (Qty: 2) @ Brake Caliper Bracket (2)

Fig. 92: Disc Brake Pads

Courtesy of GENERAL MOTORS COMPANY

NOTE: The disc brake pad equipped with wear sensor has to be mounted in upper position on the inner side of the rotor.

8. Install the disc brake pads. (1) (Qty: 2)

Fig. 93: Brake Caliper And Guide Pin Bolts Courtesy of GENERAL MOTORS COMPANY

9. Install the brake caliper assembly (1).

WARNING: Refer to Torque-to-Yield Fastener Warning

10. Install and tighten Brake Caliper Guide Pin Bolts (2) (Qty: 2) @ Rear Brake Caliper (1) to 36 N.m (27 lb ft)

11. Install the tire and wheel assembly. Refer to Tire and Wheel Removal and Installation

12. With the engine OFF, gradually apply the brake pedal to approximately 2/3 of its travel distance.

13. Slowly release the brake pedal.

15. Inspect the fluid level in the brake master cylinder reservoir.

16. Fill the brake master cylinder reservoir to the maximum-full level with GM approved brake fluid from a clean, sealed brake fluid container. Refer to Master Cylinder Reservoir Filling

17. Activate the electronic parking brake.

1. Turn the ignition ON, with the engine OFF.

2. Press the brake pedal slightly and push the electronic parking brake switch for over 5 seconds. The orange service lamp goes off and the red parking brake status lamp is flashing a few times.

FRONT BRAKE ROTOR REPLACEMENT

Special Tools

CH-41013 Rotor Resurfacing Kit

CH-42450-A Wheel Hub Resurfacing Kit

For equivalent regional tools, refer to Special Tools.

Removal Procedure

WARNING: Refer to Brake Dust Warning .

1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .

2. Remove the tire and wheel assembly. Refer to Tire and Wheel Removal and Installation .

Fig. 94: Brake Caliper Bracket Bolts

Courtesy of GENERAL MOTORS COMPANY

3. Remove the brake caliper bracket bolts (1).

CAUTION: Support the brake caliper with heavy mechanic wire, or equivalent, whenever it

is separated from its mount and the hydraulic flexible brake hose is still connected. Failure to support the caliper in this manner will cause the flexible brake hose to bear the weight of the caliper, which may cause damage to the brake hose and in turn may cause a brake fluid leak.

4. Remove the brake caliper and bracket as an assembly and support with heavy mechanics wire or equivalent.

Fig. 95: Brake Rotor Bolt

Courtesy of GENERAL MOTORS COMPANY

5. Remove the brake rotor bolt (1).

Fig. 96: Brake Rotor

Courtesy of GENERAL MOTORS COMPANY

6. Remove the brake rotor (1).

Installation Procedure

1. If installing a new brake rotor, clean the friction surfaces of the brake rotor with denatured alcohol or equivalent.

2. Using the CH-42450-A Wheel Hub Resurfacing Kit, thoroughly clean any rust or corrosion from the mating surface of the hub/axle flange.

3. Using the CH-41013 Rotor Resurfacing Kit, thoroughly clean any rust or corrosion from the mating surface of the rotor to the hub/axle flange.

Fig. 97: Brake Rotor

Courtesy of GENERAL MOTORS COMPANY

4. Install the brake rotor (1).

Fig. 98: Brake Rotor Bolt

Courtesy of GENERAL MOTORS COMPANY

CAUTION: Refer to Fastener Caution .

5. Install the brake rotor bolt (1) and tighten to 9 N.m (80 lb in).

6. Position the brake caliper and bracket assembly over the brake rotor and to the steering knuckle.

Fig. 99: Brake Caliper Bracket Bolts

Courtesy of GENERAL MOTORS COMPANY

7. Install the brake caliper bracket bolts (1).

Tighten

1. First Pass: 150 N.m (111 lb ft)

2. Final Pass: 15-30 degrees

8. Install the tire and wheel assembly. Refer to Tire and Wheel Removal and Installation .

9. Burnish the brake pads and rotors. Refer to Brake Pad and Rotor Burnishing.

REAR BRAKE ROTOR REPLACEMENT

Special Tools

CH-41013 Rotor Resurfacing Kit

CH-42450-A Wheel Hub Resurfacing Kit

CH-45059 Angle Meter

Equivalent regional tools: Special Tools

Removal Procedure

WARNING: Refer to Brake Dust Warning

NOTE: Always replace disc brake rotors in axle sets.

1. Set the electronic parking brake in the service mode.

1. Change the transmission gear to Neutral position.

2. Press the electronic park brake switch until the red parking brake status lamp is illuminating in the instrument cluster.

NOTE: Do not press the brake pedal intensely. It is sufficient if the brake tail lamps are illuminating.

3. Press the brake pedal 5 times slightly until the vacuum in the power brake booster is empty.

4. Turn the ignition ON, with the engine OFF.

5. Press the brake pedal and the electronic park brake switch for 15 seconds until the orange brake service lamp is illuminating.

6. By keeping brake pedal applied, release and re-press the electronic park brake switch for 5 seconds.

7. Release the electronic park brake switch and the brake pedal simultaneously. The rear brake calipers are retracting and the orange brake service lamp is flashing.

2. Turn OFF the ignition.

3. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle

4. Remove the tire and wheel assembly. Refer to Tire and Wheel Removal and Installation

Fig. 100: Electrical Connector, Fasteners And Wiring Harness Courtesy of GENERAL MOTORS COMPANY

5. Disconnect Electrical Connector (4)

6. Remove Fasteners (1) (Qty: 2)

7. Remove Fastener (2)

8. Remove Wiring Harness (3)

Fig. 101: Brake Caliper And Bracket Bolts Courtesy of GENERAL MOTORS COMPANY

9. Remove Rear Brake Caliper Bracket Bolts (2) (Qty: 2)

10. Remove the brake caliper assembly and support with heavy mechanics wire. (1)

Fig. 102: Rear Brake Rotor And Bolt

Courtesy of GENERAL MOTORS COMPANY

11. Remove Rear Brake Rotor Bolt (1)

12. Remove Rear Brake Rotor (2)

Installation Procedure

1. If installing a NEW brake rotor, clean the friction surfaces of the brake rotor with denatured alcohol.

2. Using the CH-42450-A resurfacing kit, thoroughly clean any rust or corrosion from the mating surface of the hub/axle flange.

3. Using the CH-41013 resurfacing kit, thoroughly clean any rust or corrosion from the mating surface of the rotor to the hub/axle flange.

Fig. 103: Rear Brake Rotor And Bolt

Courtesy of GENERAL MOTORS COMPANY

4. Install Rear Brake Rotor (2)

CAUTION: Refer to Fastener Caution

5. Install and tighten Rear Brake Rotor Bolt (1) to 9 N.m (80 lb in)

Fig. 104: Brake Caliper And Bracket Bolts Courtesy of GENERAL MOTORS COMPANY

6. Position the rear brake caliper assembly (1).

7. Install and tighten Rear Brake Caliper Bracket Bolts (2) (Qty: 2)

1. First Pass: 100 N.m (74 lb ft)

2. Final Pass: 15 - 30 degrees

Fig. 105: Electrical Connector, Fasteners And Wiring Harness Courtesy of GENERAL MOTORS COMPANY

8. Install Wiring Harness (3)

9. Install Fastener (2)

10. Install Fasteners (1) (Qty: 2)

11. Connect Electrical Connector (4)

12. Install the tire and wheel assembly. Refer to Tire and Wheel Removal and Installation

13. Lower the vehicle.

14. Activate the electronic parking brake.

1. Turn the ignition ON, with the engine OFF.

2. Press the brake pedal and the electronic parking brake switch for over 5 seconds. The orange brake service lamp turns off and the red parking brake status lamp is flashing a few times.

15. Burnish the brake pads and rotors. Refer to Brake Pad and Rotor Burnishing

FRONT BRAKE SHIELD REPLACEMENT

Special Tools

EN-45059 Angle Meter

Equivalent regional tools: Special Tools

Removal Procedure

1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .

2. Remove Front Wheel Bearing and Hub. Refer to Front Wheel Bearing and Hub Replacement

Fig. 106: Wheel Bearing/Hub, Front Brake Shield And Steering Knuckle Courtesy of GENERAL MOTORS COMPANY

3. Remove the wheel bearing/hub (1) and front brake shield (2) from the steering knuckle.

Installation Procedure

Fig. 107: Wheel Bearing/Hub, Front Brake Shield And Steering Knuckle Courtesy of GENERAL MOTORS COMPANY

1. Position the front brake shield (2) and wheel bearing/hub assembly (1) in the steering knuckle.

2. Install Front Wheel Bearing and Hub. Refer to Front Wheel Bearing and Hub Replacement

3. Remove the support and lower the vehicle.

REAR BRAKE SHIELD REPLACEMENT

Special Tools

EN-45059 Angle Meter

Equivalent regional tools: Special Tools

Removal Procedure

1. Remove the rear tire and wheel assemblies. Refer to Tire and Wheel Removal and Installation

brake hose to bear the weight of the caliper, which may cause damage to the brake hose and in turn may cause a brake fluid leak.

2. Remove Rear Brake Rotor. Refer to Rear Brake Rotor Replacement

3. Remove Rear Wheel Speed Sensor. Refer to Rear Wheel Speed Sensor Replacement

Fig. 108: Rear Shock Absorber, Bolt And Hydraulic Lift Courtesy of GENERAL MOTORS COMPANY

4. Support the rear axle with a hydraulic lift table. (3)

5. Remove Rear Shock Absorber Bolt (2)

6. Push up to the shock absorber (1) gain access to the rear wheel bearing and hub bolts.

Fig. 109: Rear Wheel Bearing And Hub Bolts Courtesy of GENERAL MOTORS COMPANY

7. Remove Bolts (1) (Qty: 4)

Fig. 110: Rear Brake Caliper Mount Plate, Rear Brake Shield, Rear Wheel Bearing and Hub Assembly Courtesy of GENERAL MOTORS COMPANY

8. Remove Rear Wheel Bearing and Hub Assembly (1)

9. Remove the rear brake shield (2).

10. Remove the rear brake caliper mount plate (3).

Installation Procedure

Fig. 111: Rear Brake Caliper Mount Plate, Rear Brake Shield, Rear Wheel Bearing and Hub Assembly Courtesy of GENERAL MOTORS COMPANY

1. Install the rear brake caliper mount plate (3).

2. Install the rear brake shield (2).

3. Install Rear Wheel Bearing and Hub Assembly (1)

Fig. 112: Rear Wheel Bearing And Hub Bolts Courtesy of GENERAL MOTORS COMPANY

CAUTION: Refer to Fastener Caution

4. Apply thread locking adhesive to the fasteners.

5. Install and tighten Bolts (1) (Qty: 4)

1. First Pass: 50 Nm. (37 lb ft).

2. Final Pass: 30 - 45 degrees, use the EN-45059 meter

Fig. 113: Rear Shock Absorber, Bolt And Hydraulic Lift Courtesy of GENERAL MOTORS COMPANY

NOTE: Service may offer bolts without micro-encapsulated thread locking adhesive. If this is the case, apply thread locking adhesive to the bolt.

6. Support the rear axle with a tall jack stand near the shock absorber.

7. Install, but do NOT tighten Rear Shock Absorber Bolt (2)

8. Install Rear Wheel Speed Sensor. Refer to Rear Wheel Speed Sensor Replacement

9. Install Rear Brake Rotor. Refer to Rear Brake Rotor Replacement - Install

10. Install Tire and Wheel. Refer to Tire and Wheel Removal and Installation

11. Lower the vehicle.

Fig. 114: Rear Shock Absorber Bolt

Courtesy of GENERAL MOTORS COMPANY

NOTE: Tighten the bolt with vehicle standing on the ground.

12. Tighten Rear Shock Absorber Bolt (1) to 100 N.m (74 lb ft)

BRAKE ROTOR ASSEMBLED LATERAL RUNOUT CORRECTION

NOTE: Brake rotor thickness variation MUST be checked BEFORE checking for assembled lateral runout (LRO). Thickness variation exceeding the maximum acceptable level can cause brake pulsation. Refer to Brake Rotor Thickness Variation Measurement

Brake rotor assembled lateral runout (LRO) exceeding the maximum allowable specification can cause thickness variation to develop in the brake rotor over time, usually between 4800 - 11300 km (3,000 - 7,000 mi). Refer to Brake Rotor Assembled Lateral Runout Measurement

Review the following acceptable methods for bringing the brake rotor assembled LRO to within specifications. Determine which method to use for the specific vehicle being repaired.

The indexing method of correcting assembled LRO is most effective when the LRO specification is only exceeded by a relatively small amount: 0.025 - 0.127 mm (0.001 - 0.005 in). Indexing is used to achieve the best possible match of high spots to low spots between related components. Refer to Brake Rotor Assembled Lateral Runout Correction - Indexing

The on-vehicle brake lathe method is used to bring the LRO to within specifications through compensating for LRO while refinishing the brake rotor. Refer to Brake Rotor Assembled Lateral Runout Correction - On Vehicle Lathe

If the assembled LRO cannot be corrected using these methods, then other components must be suspected as causing and/or contributing to the LRO concern.

BRAKE ROTOR ASSEMBLED LATERAL RUNOUT CORRECTION - INDEXING

NOTE: This Procedure is not used in Europe

Special Tools

CH-45101-100 Conical Brake Rotor Washers

For equivalent regional tools, refer to Special Tools.

Fig. 115: Conical Brake Rotor Washer And Lug Nut Courtesy of GENERAL MOTORS COMPANY

WARNING: Refer to Brake Dust Warning .

Brake rotor assembled LRO exceeding the maximum allowable specification can cause thickness variation to develop in the brake rotor over time, usually between 4800 - 11300 km (3,000 - 7,000 mi). Refer to Brake Rotor Assembled Lateral Runout Measurement

1. Remove the CH-45101-100 Conical Brake Rotor Washers and the lug nuts that were installed during the assembled LRO measurement procedure.

2. Inspect the mating surface of the hub/axle flange and the brake rotor to ensure that there are no foreign particles or debris remaining.

3. Index the brake rotor in a different orientation to the hub/axle flange.

4. Hold the rotor firmly in place against the hub/axle flange and install one of the CH-45101-100 Conical Brake Rotor Washers (1) and one lug nut (2) onto the upper-most wheel stud.

5. Continue to hold the rotor secure and tighten the lug nut firmly by hand.

Fig. 116: Conical Brake Rotor Washers And Lug Nuts Courtesy of GENERAL MOTORS COMPANY

6. Install the remaining CH-45101-100 Conical Brake Rotor Washers and lug nuts onto the wheel studs and tighten the nuts firmly by hand in a star-pattern.

7. Tighten the lug nuts in a star-pattern to specification, in order to properly secure the rotor. Refer to Tire and Wheel Removal and Installation

8. Measure the assembled LRO of the brake rotor. Refer to Brake Rotor Assembled Lateral Runout Measurement

9. Compare the amount of change between this measurement and the original measurement.

10. If this measurement is within specifications, proceed to step 14.

11. If this measurement still exceeds specifications, repeat steps 1 - 9 until the best assembled LRO measurement is obtained.

12. Matchmark the final location of the rotor to the wheel studs if the orientation is different than it was originally.

13. If the brake rotor assembled LRO measurement still exceeds the maximum allowable specification, refer to

Brake Rotor Assembled Lateral Runout Correction.

14. If the brake rotor assembled LRO is within specification, install the brake caliper and depress the brake pedal several times to secure the rotor in place before removing the CH-45101-100 Conical Brake Rotor Washers and the lug nuts.

BRAKE ROTOR ASSEMBLED LATERAL RUNOUT CORRECTION - CORRECTION PLATES

NOTE: This procedure not used in Europe

Special Tools

CH-45101-100 Conical Brake Rotor Washers

For equivalent regional tools, refer to Special Tools.

Fig. 117: Correction Plate, High Spot Mark And V-Shaped Notch Courtesy of GENERAL MOTORS COMPANY

WARNING: Refer to Brake Dust Warning .

1. Rotate the brake rotor to position the high spot, identified and marked during the brake rotor assembled LRO measurement procedure, to face upward.

2. Remove the CH-45101-100 Conical Brake Rotor Washers and the lug nuts that were installed during the assembled LRO measurement procedure and/or the indexing correction procedure.

3. Inspect the mounting surface of the hub/axle flange and the brake rotor to ensure that there are no foreign particles or debris remaining.

4. Select the correction plate, following the manufacturer's instructions, which has a specification closest to the assembled LRO measurement.

For example: If the assembled LRO measurement was 0.076 mm (0.003 in), the 0.076 mm (0.003 in) correction plate would be used. If the measurement was 0.127 mm (0.005 in), the 0.152 mm (0.006 in) correction plate would be used.

5. Determine the positioning for the correction plate (1) using the high spot mark (3) made during the brake rotor assembled LRO measurement procedure.

NOTE: Do NOT install used correction plates in an attempt to correct brake rotor assembled LRO.

Do NOT stack up, or install more than one correction plate onto one hub/axle flange location, in an attempt to correct brake rotor assembled LRO.

6. Install the correction plate (1) onto the hub/axle flange, with the V-shaped notch (2) orientated to align with the high spot mark (3), that was positioned to face upward.

Fig. 118: Conical Brake Rotor Washer And Lug Nut Courtesy of GENERAL MOTORS COMPANY

7. Install the brake rotor to the hub/axle flange. Use the matchmark made prior to removal for proper orientation to the flange.

8. Hold the rotor firmly in place against the hub/axle flange and install one of the CH-45101-100 Conical Brake Rotor Washers (1) and one lug nut (2) onto the upper-most wheel stud.

9. Continue to hold the rotor secure and tighten the lug nut firmly by hand.

Fig. 119: Conical Brake Rotor Washers And Lug Nuts Courtesy of GENERAL MOTORS COMPANY

10. Install the remaining CH-45101-100 Conical Brake Rotor Washers and lug nuts onto the wheel studs and tighten the nuts firmly by hand in a star-pattern.

11. Tighten the lug nuts in a star-pattern to specification, in order to properly secure the rotor. Refer to Tire and Wheel Removal and Installation

12. Measure the assembled LRO of the brake rotor. Refer to Brake Rotor Assembled Lateral Runout Measurement

13. If the brake rotor assembled LRO measurement still exceeds the maximum allowable specification, refer to

Brake Rotor Assembled Lateral Runout Correction.

14. If the brake rotor assembled LRO measurement is within specification, install the brake caliper and depress the brake pedal several times to secure the rotor in place before removing the CH-45101-100 Conical Brake Rotor Washers and the lug nuts.

BRAKE ROTOR ASSEMBLED LATERAL RUNOUT CORRECTION - ON VEHICLE LATHE

NOTE: This procedure is not used in Europe.

Special Tools

CH-45101-100 Conical Brake Rotor Washers

For equivalent regional tools, refer to Special Tools.

WARNING: Refer to Brake Dust Warning .

1. Ensure that the caliper and caliper bracket that are already being supported, are clear from contacting any rotating components, such as the brake rotor.

2. Remove the CH-45101-100 Conical Brake Rotor Washers and the lug nuts that were installed during the assembled LRO measurement procedure and/or the indexing correction procedure.

3. Inspect the mounting surface of the hub/axle flange and the brake rotor to ensure that there are no foreign particles or debris remaining.

4. Set up the lathe, following the manufacturer's instructions.

5. Refinish the brake rotor, following the brake lathe manufacturer's instructions.

6. After each successive cut, inspect the brake rotor thickness. Refer to Brake Rotor Thickness Measurement

7. If at any time the brake rotor exceeds the minimum allowable thickness after refinish specification, the brake rotor must be replaced. After replacing the rotor, proceed to step 10.

8. After refinishing the brake rotor, use the following procedure in order to obtain the desired non-directional finish:

1. Follow the brake lathe manufacturer's recommended speed setting for applying a non-directional finish.

2. Using moderate pressure, apply the non-directional finish:

If the lathe is equipped with a non-directional finishing tool, apply the finish with 120-grit aluminum oxide sandpaper.

If the lathe is not equipped with a non-directional finishing tool, apply the finish with a sanding block and 150-grit aluminum oxide sandpaper.

3. After applying a non-directional finish, clean each friction surface of the brake rotor with denatured alcohol, or an equivalent approved brake cleaner.

9. Remove the lathe from the vehicle.

10. Measure the assembled LRO of the brake rotor. Refer to Brake Rotor Assembled Lateral Runout Measurement

11. If the brake rotor assembled LRO measurement still exceeds the maximum allowable specification, refer to

Brake Rotor Assembled Lateral Runout Correction.

12. If the brake rotor assembled LRO is within specification, install the brake caliper and depress the brake pedal several times to secure the rotor in place before removing the CH-45101-100 Conical Brake Rotor Washers and the lug nuts.

BRAKE ROTOR REFINISHING

Special Tools

CH-41013 Rotor Resurfacing Kit

CH-42450-A Wheel Hub Resurfacing Kit

For equivalent regional tools, refer to Special Tools.

WARNING: Refer to Brake Dust Warning .

NOTE: The disc brake rotors do not require refinishing as part of routine brake system service. New disc brake rotors do not require refinishing.

Do not refinish disc brake rotors in an attempt to correct the following conditions:

Brake system noise - squeal, growl, groan

Uneven and/or premature disc brake pad wear

Superficial or cosmetic corrosion/rust of the disc brake rotor friction surface

Scoring of the disc brake rotor friction surface less than the maximum allowable specification

Before refinishing a brake rotor, the rotor MUST first be checked for adequate thickness to allow the rotor to be refinished and remain above the minimum allowable thickness after refinish specification. Refer to Brake Rotor Thickness Measurement

Disc brake rotors should only be refinished if they have adequate thickness to be refinished and if one or more of the following conditions exist:

Thickness variation in excess of the maximum allowable specification Excessive corrosion/rust and/or pitting

Cracks and/or heat spots

Excessive blueing discoloration

Scoring of the disc brake rotor surface in excess of the maximum allowable specification

Disc brake rotors may need to be refinished as part of the process for correcting brake rotor assembled lateral runout (LRO) that exceeds the maximum allowable specification.

NOTE: If the vehicle is equipped with cross-drilled rotors, use a lathe with positive rake tooling. This setup requires less cutting pressure, which will result in less vibration, and a better surface finish. Also, use a vibration dampener when cutting. Otherwise, refinish according to the following instructions.

NOTE: Whenever the brake rotor has been separated from the hub/axle flange, clean any rust or contaminants from the hub/axle flange and the brake rotor mating surfaces. Failure to do this may result in increased assembled lateral runout (LRO) of the brake rotor, which could lead to brake pulsation.

1. Using the CH-42450-A Wheel Hub Resurfacing Kit, thoroughly clean any rust or corrosion from the mating

surface of the hub/axle flange.

2. Using the CH-41013 Rotor Resurfacing Kit, thoroughly clean any rust or corrosion from the mating surface and mounting surface of the brake rotor.

3. Inspect the mating surfaces of the hub/axle flange and the rotor to ensure that there are no foreign particles or debris remaining.

4. Mount the brake rotor to the brake lathe according to the lathe manufacturer's instructions, ensuring that all mounting attachments and adapters are clean and free of debris.

5. Ensure that any vibration dampening attachments are securely in place.

6. With the brake lathe running, slowly bring in the cutting tools until they just contact the brake rotor friction surfaces.

7. Observe the witness mark on the brake rotor. If the witness mark extends approximately three-quarters or more of the way around the brake rotor friction surface on each side, the brake rotor is properly mounted to the lathe.

8. If the witness mark does not extend three-quarters or more of the way around the brake rotor, re-mount the rotor to the lathe.

9. Following the brake lathe manufacturer's instructions, refinish the brake rotor.

10. After each successive cut, inspect the brake rotor thickness. Refer to Brake Rotor Thickness Measurement

11. If at any time the brake rotor exceeds the minimum allowable thickness after refinish specification, the brake rotor must be replaced.

12. After refinishing the brake rotor, use the following procedure in order to obtain the desired non-directional finish:

1. Follow the brake lathe manufacturer's recommended speed setting for applying a non-directional finish.

2. Using moderate pressure, apply the non-directional finish:

If the lathe is equipped with a non-directional finishing tool, apply the finish with 120-grit aluminum oxide sandpaper.

If the lathe is not equipped with a non-directional finishing tool, apply the finish with a sanding block and 150-grit aluminum oxide sandpaper.

NOTE: Thoroughly cleaning the brake rotor will prevent the possible transfer of finite metal dust left as a by-product of machining to the brake pad material during the burnishing process, thereby reducing the possibility for brake squeal or other brake noises to occur.

3. After applying a non-directional finish, clean each friction surface of the brake rotor with a solution of mild dish washing detergent and water, or a GM approved brake cleaner and a clean shop towel to remove metal particles remaining from machining. Repeat the cleaning process if necessary to remove all metal particles.

13. Remove the brake rotor from the brake lathe.

14. Measure the assembled LRO of the brake rotor to ensure optimum performance of the disc brakes. Refer to

Brake Rotor Assembled Lateral Runout Measurement

15. If the brake rotor assembled LRO measurement exceeds the specification, bring the LRO to within specifications. Refer to Brake Rotor Assembled Lateral Runout Correction

DESCRIPTION AND OPERATION

DISC BRAKE SYSTEM DESCRIPTION AND OPERATION

Fig. 120: Brake Caliper Piston, Rotor And Brake Pads Courtesy of GENERAL MOTORS COMPANY

CAUTION: Refer to Brake Caliper Caution .

The brake caliper is single piston type; and is installed on knuckle by two mounting bolts. Brake caliper transforms hydraulic pressure generated by depressing brake pedal into braking force. The braking force evenly acts on the piston (1) and the bottom of brake caliper cylinder bore, and then move the piston outward and slide brake caliper inward so that there generates a clamping effect on brake rotor (2). The clamping effect forces brake pad (3) to attach to brake rotor, and the resulting friction will make vehicles stop.

When maintaining the brake caliper, replace all parts included in repair sets.

Lubricate the rubber parts with clean brake fluid to make assembly easier.

Do not apply compressed air to brake parts with workshop with lubricant, otherwise the rubber parts may be damaged.

If any hydraulic component is removed or disconnected, it may be necessary to bleed all or part of the brake system.

Replace whole brake pad (3) according to service parts in the maintenance package. The torque values are specified for dry, non-lubricated fasteners.

Perform the service operations on a clean bench, free from all mineral oil materials.

Gap Calibration

Fig. 121: Sectional View Of Pads, Piston Seal And Piston Courtesy of GENERAL MOTORS COMPANY

When the hydraulic pressure acts on the piston (3), the piston moves left. The piston seals (2) exert pressure on the piston and move together with the cylinder. However, parts of the piston seals are fixed in the grooves of the cylinder. As shown, the shape of seals deforms toward the direction of piston.

When the pressure on the brake pedal is removed and the hydraulic pressure on the piston is released, there generates recovery elasticity on the seals. The force pushes the piston to the right side and return to its original position.

When the brake pad (1) exhibits wear, and the gap between the brake rotor and brake pad gets much larger, the piston moves farther.

Seals may further deform. Because the end of seals is fixed in the groove of the cylinder, the deformation is limited in the above-mentioned scope. Pistons further move to fill the gap. When the piston returns to the same position, the rubber seals resume original shape, and the gap between brake rotor and brake pad keeps the original level.

SPECIAL TOOLS AND EQUIPMENT

SPECIAL TOOLS

Illustration

Tool Number/Description