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.


Object Number: 900989  Size: SH

Notice: There is a first design and second design of brake pipe flare for the hydraulic brake pipes and system components used on this vehicle. Do NOT mis-match flare types. If the flare types are mis-matched, damage to the pipes and/or components, and/or a brake fluid leak may occur.

   • First design, ISO flare (1)
   • Second design, double inverted flare (2)

Removal Procedure


    Object Number: 931316  Size: SH
  1. Disconnect the electrical connector (1) from the brake fluid level sensor.

  2. Object Number: 931327  Size: SH
  3. Disconnect the brake pipes from the master cylinder.
  4. Important: Install a rubber cap or plug to the exposed brake pipe fitting ends in order to prevent brake fluid loss and contamination.

  5. Plug the open brake pipe ends.

  6. Object Number: 926593  Size: SH
  7. Remove master cylinder mounting nuts.
  8. Remove the master cylinder from the vehicle.
  9. Drain the master cylinder reservoir of all brake fluid.

Installation Procedure


    Object Number: 926593  Size: SH
  1. Bench bleed the master cylinder. Refer to Master Cylinder Bench Bleeding .
  2. Install the master cylinder to the brake booster.
  3. 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.

  4. Install the master cylinder mounting nuts.
  5. Tighten
    Tighten the master cylinder mounting nuts to 25 N·m (18 lb ft).


    Object Number: 931327  Size: SH
  6. Remove the plugs from the brake pipes.
  7. Connect the brake pipes to the master cylinder.
  8. Tighten

        • Tighten the brake pipe fittings first design, ISO flare, to 19 N·m (14 lb ft).
        • Tighten the brake pipe fittings second design, double inverted flare, to 18 N·m (13 lb ft).

    Object Number: 931316  Size: SH
  9. Connect the electrical connector (1) to the brake fluid level sensor.
  10. Bleed the hydraulic brake system. Refer to Hydraulic Brake System Bleeding .