Front

Brake Caliper Overhaul - Front

1. Remove the brake caliper from the vehicle.

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.

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.





2. Remove the caliper piston by directing low pressure compressed air into the brake caliper through the fluid inlet hole.

Important: Care must be used when removing the piston boot and seal from the caliper. Use a small plastic or wood tool for removal.





3. Remove the piston boot (2) from the caliper (1).
4. Remove the piston seal (4) from the caliper (1).
5. Remove the bleeder valve (5) and cap (6) from the caliper (1).
6. Clean all of the parts. Use clean denatured alcohol.
7. Dry all of the parts with low pressure non-lubricated filtered air.
8. Blow out all of the passages in the caliper body and the bleeder valve.
9. Inspect all of the parts as follows:
^ Piston - Inspect for scoring, nicks, cracks wear, or corrosion. Replace the piston if any damage is found.
^ Caliper Bore - Inspect for scoring, nicks, cracks, wear, or corrosion. Use crocus cloth to polish out light corrosion. Otherwise, replace the caliper. Do not hone the caliper bore.
^ Seal groove - Inspect for nicks or burrs in the seal groove in the caliper bore. If found, replace the caliper.

Notice: Refer to Fastener Notice in Service Precautions

10. Install the bleeder valve cap and bleeder valve into the caliper.
Tighten the bleeder valve to 13 Nm (115 lb in).
11. Install the new piston seal. Lubricate the seal with new Delco Supreme 11 (GM P/N 12377967) or equivalent brake fluid before installing.





12. Install the new piston boot over the piston.
13. Using a caliper piston dust boot seal installer, or equivalent tool, that will fully seat the dust boot seal for the seal counterbore diameter and the piston bore diameter specified.
Specification
^ Brake caliper piston dust boot seal counterbore diameter 78.08 mm (3.074 inch).
^ Brake caliper piston bore diameter 63.43 mm (2.50 inch).

14. Install the caliper onto the vehicle.