GM Service Manual Online
For 1990-2009 cars only

Caution: Refer to Brake Fluid Irritant Caution in the Preface section.

Notice: Refer to Brake Fluid Effects on Paint and Electrical Components Notice in the Preface section.

Removal Procedure

  1. Apply the park brake and block the wheels.

  2. Object Number: 793135  Size: SH
  3. Disconnect the electrical connector from the brake fluid level sensor, if applicable.
  4. Remove the driver side upper fender support.
  5. Important: Install a rubber cap or plug to the exposed brake pipe fitting ends in order to prevent brake fluid loss and contamination.

  6. Disconnect the brake pipes from the master cylinder.
  7. Plug the open brake pipe ends.

  8. Object Number: 1372862  Size: SH
  9. For vehicles with JL4, crimp the hose (4) at the master cylinder to prevent fluid from leaking out.
  10. Remove the clamp (5) and hose (4) from the reservoir. Plug the port in the reservoir.

  11. Object Number: 793137  Size: SH
  12. Remove the master cylinder mounting nuts.
  13. Remove the master cylinder from the vehicle.
  14. Remove the master cylinder reservoir. Refer to Master Cylinder Reservoir Replacement .

Installation Procedure

  1. Install the master cylinder reservoir. Refer to Master Cylinder Reservoir Replacement .
  2. Bench bleed the master cylinder. Refer to Master Cylinder Bench Bleeding .

  3. Object Number: 793137  Size: SH
  4. Install the master cylinder to the vehicle.
  5. Notice: Refer to Fastener Notice in the Preface section.

  6. Install the master cylinder mounting nuts.
  7. Tighten
    Tighten the nuts to 36 N·m (27 lb ft).


    Object Number: 1372862  Size: SH
  8. For vehicles with JL4, remove the plug from the reservoir port and install the hose (4) and clamp (5) to the reservoir.
  9. Remove the crimping tool from the hose (4).

  10. Object Number: 793135  Size: SH
  11. Remove the rubber cap or plug from the exposed brake pipe fitting ends.

  12. Connect the brake pipes.
  13. Tighten
    Tighten the pipe fittings to 25 N·m (18 lb ft).

  14. Connect the electrical connector to the brake fluid level sensor.
  15. Install the driver side upper fender support.
  16. Bleed the hydraulic brake system. Refer to Hydraulic Brake System Bleeding .
  17. Release the park brake and unblock the wheels.