GM Service Manual Online
For 1990-2009 cars only

Disassembly Procedure


    Object Number: 177039  Size: SH
  1. Remove the front brake caliper. Refer to Brake Caliper Replacement .
  2. Caution: 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.

    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. Remove the piston by applying low-pressure compressed air into the caliper inlet hole. The piston will come out through the piston boot.
  4. Inspect the piston for the following conditions:
  5. • Scoring
    • Gouges
    • Corrosion
    •  Replace the piston if any of the above conditions are found.

    Object Number: 177049  Size: SH
  6. Remove the caliper boot (2). Do not scratch the housing bore.

  7. Object Number: 177058  Size: SH

    Notice: Do not use a metal tool for seal removal. Damage to the caliper bore or the seal grooves can result.

  8. Remove the piston seal (4) from the groove in the caliper bore. Use a small wooden or plastic tool.
  9. Inspect the caliper bore and the seal grooves for the following conditions:
  10. • Scoring
    • Nicks
    • Corrosion
    • Wear
  11. Use a crocus cloth in order to polish out light corrosion.
  12. Replace the caliper housing (3) if corrosion in and around the seal groove cannot be cleaned with a crocus cloth.

  13. Object Number: 177063  Size: SH
  14. Inspect the bolt boots (2) for the following conditions:
  15. • Cuts
    • Tears
    • Deterioration
  16. Replace any damaged boots (2).
  17. Inspect the caliper bolts for corrosion or damage. Replace any corroded bolts. Do not attempt to polish away corrosion.
  18. Inspect the seal groove in the caliper bore for nicks or burrs. Replace the caliper if the seal groove is damaged.

  19. Object Number: 177058  Size: SH
  20. Remove the bleeder valve cap (1) and the bleeder valve (2) from the caliper housing (3).
  21. Clean all the parts in denatured alcohol.
  22. Dry all the parts with filtered, non-lubricated compressed air.
  23. Blow out all the passages in the caliper housing and the bleeder valve. Use filtered, non-lubricated compressed air.

Assembly Procedure

Tools Required

J 36349 Front Dust Boot Seal Installer


    Object Number: 177058  Size: SH

    Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  1. Install the bleeder valve (2) and the bleeder valve cap (1) to the caliper housing.
  2. Tighten
    Tighten the bleeder valve to 13 N·m(115 lb in).

  3. Install a new lubricated piston seal into the caliper bore grooves. Verify that the piston seal is not twisted.

  4. Object Number: 177051  Size: SH
  5. Install the lubricated boot (1) onto the piston (2).
  6. Lubricate the piston outside diameter with clean brake fluid.

  7. Object Number: 177056  Size: SH
  8. Install the piston and the boot into the bore of the caliper. Push the piston to the bottom of the bore.
  9. Seat the caliper boot in the caliper housing (1) counterbore using the J 36349 .
  10. Install the front brake caliper. Refer to Brake Caliper Replacement .