Front Brake Caliper Overhaul (J55)

Single Use Fasteners and Components Front Brake Caliper Piston Boot [6x] Front Brake Caliper Piston Seal [6x] Front Brake Hose Washer [2x]

Warning

The battery must be disconnected to prevent the brake master cylinder from pressurizing the hydraulic system during its automated self diagnostic tests that can possibly occur when a door is opened or the key transmitter is activated. Failure to follow this precaution may cause 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.

Warning

Brake Dust Warning

Warning

Brake Fluid Irritant Warning

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. Removal Procedure Remove the front brake caliper. Front Brake Caliper Replacement Disassembly Procedure

Front Brake Caliper Overhaul (J55) — figure 1

1. Using a plastic tool, remove and DISCARD the 3 front brake caliper piston boots (3).
2. Place a 25 mm (1 in) block of wood between the caliper housing and the caliper pistons.

Note

Protect the caliper painted surfaces while using the C-Clamp.

3. Install a large C-clamp over the body of the brake caliper with the C-clamp ends against the outboard surface of the caliper body and against the block of wood.
4. Remove the 3 front brake caliper pistons (2) from the caliper bore by directing low pressure compressed air into the caliper bore through the brake hose inlet port.
5. Remove the C-clamp from the caliper.
6. Remove the block of wood from the caliper.
7. Using a plastic tool, remove and DISCARD the 3 front brake caliper piston seals (1).

Front Brake Caliper Overhaul (J55) — figure 2

8. Using a plastic tool, remove and DISCARD the 3 front brake caliper piston boots (1).
9. Place a 25 mm (1 in) block of wood between the caliper housing and the caliper pistons.

Note

Protect the caliper painted surfaces while using the C-Clamp.

10. Install a large C-clamp over the body of the brake caliper with the C-clamp ends against the inboard surface of the caliper body and against the block of wood.
11. Remove the 3 front brake caliper pistons (2) from the caliper bore by directing low pressure compressed air into the caliper bore through the brake hose inlet port.
12. Remove the C-clamp from the caliper.
13. Remove the block of wood from the caliper.
14. Using a plastic tool, remove and DISCARD the 3 front brake caliper piston seals (3).

Front Brake Caliper Overhaul (J55) — figure 3

15. Front Brake Caliper Bleeder Valve Cap (1) » Remove [2x]

16. Front Brake Caliper Bleeder Valve (2) » Remove [2x]

17. Clean the brake caliper piston bores with denatured alcohol, or equivalent.

18. Inspect the caliper bores for cracks, scoring, pitting and corrosion.

19. If cracks, scoring, pitting or corrosion exists, replace the brake caliper. Assembly Procedure

20. Front Brake Caliper Bleeder Valve (2) » Install and hand tighten [2x]

21. Lubricate the 3 NEW front brake caliper piston seals (3) with GM approved brake fluid from a clean, sealed brake fluid container. Adhesives, Fluids, Lubricants, and Sealers

22. Install the 3 NEW front brake caliper piston seals (3) into the brake caliper housing grooves. Ensure the front brake caliper piston seals (3) are properly seated in the caliper housing grooves and are not distorted.

23. Install the 3 NEW front brake caliper piston boots (1) into the dust boot grooves on the 3 front brake caliper pistons (2).

24. Install the 3 front brake caliper pistons (2) into the caliper bores.

25. Install the 3 front brake caliper piston boots (1) into the front brake caliper housing.

26. Fully seat the 3 front brake caliper pistons (2) into the brake caliper bores.

27. Lubricate the 3 NEW front brake caliper piston seals (1) with GM approved brake fluid from a clean, sealed brake fluid container. Adhesives, Fluids, Lubricants, and Sealers

28. Install the 3 NEW front brake caliper piston seals (1) into the brake caliper housing grooves. Ensure the front brake caliper piston seals (1) are properly seated in the caliper housing grooves and are not distorted.

29. Install the 3 NEW front brake caliper piston boots (3) into the dust boot grooves on the 3 front brake caliper pistons (2).

30. Install the 3 front brake caliper pistons (2) into the caliper bores.

31. Install the 3 front brake caliper piston boots (3) into the front brake caliper housing.

32. Fully seat the 3 front brake caliper pistons (2) into the brake caliper bores. Installation Procedure Install the front brake caliper. Front Brake Caliper Replacement