GM Service Manual Online
For 1990-2009 cars only

Disassembly Procedure


    Object Number: 201643  Size: LH
  1. Mark the pressure cap (4) and the chamber assembly (7) in relation to the clamp ring assembly (2).
  2. Remove the air brake chamber clevis (5) and the nut (6).
  3. Pull out the pushrod (9).
  4. Clamp the pushrod (9) using locking-type pliers.
  5. Remove the nuts and the bolts.

  6. Object Number: 201666  Size: SH
  7. Remove the clamp ring assembly.

  8. Object Number: 201671  Size: SH
  9. Remove the pressure cap.

  10. Object Number: 201669  Size: SH
  11. Release the locking-type pliers from the pushrod.

  12. Object Number: 201673  Size: SH
  13. Remove the diaphragm.

  14. Object Number: 201674  Size: SH
  15. Remove the pushrod.

  16. Object Number: 201676  Size: SH
  17. Remove the return spring.

  18. Object Number: 201643  Size: LH

    Important: Replace all worn and/or damaged parts.

  19. Inspect the inside of the chamber assembly (7) for corrosion.
  20. Replace the chamber assembly (7) if corrosion is found.
  21. Inspect the return spring (8).
  22. Inspect the pushrod (9).
  23. Inspect the clamp ring assembly (2).

Assembly Procedure


    Object Number: 201676  Size: SH
  1. Install the return spring into the chamber assembly.

  2. Object Number: 201674  Size: SH

    Important: Compress the return spring and clamp the pushrod in place with locking-type pliers.

  3. Install the pushrod into the chamber assembly.

  4. Object Number: 201673  Size: SH
  5. Install the diaphragm into the chamber assembly.

  6. Object Number: 201671  Size: SH
  7. Install the pressure cap onto the chamber assembly.

  8. Object Number: 201666  Size: SH
  9. Install the clamp ring assembly.

  10. Object Number: 201643  Size: LH

    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.

    Important: Align the marks made during the disassembly.

  11. Install the bolts (1) and the nuts (3).
  12. Tighten
    Tighten the nuts to 34 N·m (25 lb ft).


    Object Number: 201669  Size: SH
  13. Release the locking-type pliers.

  14. Object Number: 201643  Size: LH
  15. Loose fit the nut and the air brake chamber clevis to the pushrod.
  16. Install the nut (6) and the air brake chamber clevis (5) to the pushrod (9).