Brake Caliper Overhaul - Front

Brake Caliper Overhaul - Front

Tools Required
^ J 8092 Universal Driver
^ J 45507 Caliper Boot Seal Installer

Caution: Refer to Brake Fluid Irritant Caution in Cautions and Notices.

Notice: Refer to Brake Fluid Effects on Paint and Electrical Components Notice in Cautions and Notices.

Disassembly Procedure

Important:
^ Replace all the components included in the repair kits used to service this brake caliper.
^ Lubricate the rubber parts with new Delco Supreme 11, GM P/N 12377967 (Canadian P/N 992667) or equivalent DOT-3 brake fluid to make assembly easier.
^ If any hydraulic component is removed or disconnected, it may be necessary to bleed all or part of the brake system.
^ The torque values specified are for dry, non-lubricated fasteners.
^ Perform the service operations on a clean bench, free from all mineral oil materials.

Caution; Do not place your fingers in front of the piston in order to catch or protect the piston while applying compressed air. This could result in serious injury.

1. Remove the brake caliper from the vehicle. Refer to Brake Caliper Replacement - Front.
2. Drain the brake fluid from the brake caliper.

Notice: 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.

3. Place a 25 mm (1 in) block of wood between the caliper and the piston.
4. Install a large C-clamp over the body of the brake caliper with the C-clamp ends against the rear of the caliper body and against the block of wood.
5. Carefully remove the brake caliper piston by directing low pressure compressed air into the brake caliper inlet hole.
6. Remove the C-clamp form the caliper.
7. Remove the block of wood from the caliper.
8. Install clean cloths to pad the interior of the caliper housing between the remaining caliper piston and the caliper body.
9. To cover the open caliper bore place a 25 mm (1 in) block of wood between the caliper body and the brake caliper dust boot seal.
10. Install a large C-clamp over the body of the brake caliper with the C-clamp ends against the rear of the caliper body and against the block of wood.
11. Carefully remove the brake caliper piston by directing low pressure compressed air into the brake caliper inlet hole.
12. Remove the C-clamp form the caliper.
13. Remove the block of wood from the caliper.
14. Using a small wooden or plastic tool, remove the piston dust boot seal (2) from the seal counter-bore in the brake caliper and discard the boot seal.
15. Using a small wooden or plastic tool, remove the piston seal (1) from the brake caliper bore and discard the piston seal.
16. Remove the brake caliper bleeder valve cap.
17. Remove the brake caliper bleeder valve (1).

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

18. Inspect the brake caliper mounting bracket guide surfaces for corrosion and wear. Remove and replace the brake caliper mounting bracket if damaged or worn.
19. Clean the brake caliper piston bores and seal counter-bores with denatured alcohol, or equivalent.
20. Clean the brake caliper pistons with denatured alcohol, or equivalent.
21. Dry the caliper piston bores and counter-bores with non-lubricated, filtered air.
22. Dry the brake caliper pistons with non-lubricated, filtered air.
23. Inspect the caliper bores for cracks, scoring, pitting, excessive corrosion.
24. If light corrosion is present in the caliper bores, attempt to remove the imperfection with a fine emery paper. If the imperfection cannot be removed, replace the caliper assembly.
25. If cracks, scoring, pitting, and excessive corrosion are present in the caliper bores, replace the caliper assembly.
26. Inspect the caliper pistons for cracks, scoring, and~or damage. Replace the caliper pistons if any of these conditions exist.

Assembly Procedure

Notice: Refer to Fastener Notice in Cautions and Notices.

1. Install the brake caliper bleeder valve (1).
Tighten
Tighten the brake caliper bleeder valve to 14 N.m (124 lb in).
2. Install the brake caliper bleeder valve cap.
3. Lubricate the new piston seals (1) with Delco Supreme 11, GM P/N 12377967 (Canadian P/N 992667) or equivalent DOT-3 brake fluid from a clean, sealed brake fluid container.
4. Install lubricated piston seals (1) into the brake caliper bore seal grooves.
5. Make sure the seals are not twisted.
6. Lubricate the brake caliper bores and the pistons (3) with brake fluid.
7. Install the caliper pistons (3) into the caliper bores.
8. Install the new piston dust boot seals (2) over the pistons.
9. Assemble the J 8092 and the J 45507
10. Complete the following for both caliper piston dust boot seals (2).
10.1. Using J 8092 and J 45507 fully seat the dust boot seal into the caliper.
10.2. Make sure the caliper piston dust boot is properly seated into the groove in the brake caliper bore.
11. Install the caliper to the vehicle. Refer to Brake Caliper Replacement - Front. Brake Caliper Replacement - Front