GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

Caution: Brake fluid may irritate eyes and skin. In case of contact, take the following actions:

   • Eye contact--rinse thoroughly with water.
   • Skin contact--wash with soap and water.
   • If ingested--consult a physician immediately.

Notice: Brake fluid will damage electrical connections and painted surfaces. Use shop cloths, suitable containers, and fender covers to prevent brake fluid from contacting these areas. Always re-seal and wipe off brake fluid containers to prevent spills.


    Object Number: 470267  Size: SH
  1. Disconnect the reservoir fluid level connector (2).
  2. Clean the reservoir and the master cylinder.
  3. Remove the reservoir. Refer to Master Cylinder Reservoir Replacement .

  4. Object Number: 470168  Size: SH
  5. If the vehicle has ABS, disconnect the brake pipes (1,4) from the proportioning valve (3).
  6. Disconnect the brake pipes from the master cylinder.
  7. Remove the nuts that retain the master cylinder to the brake booster.
  8. If the vehicle does not have ABS, remove the master cylinder from the brake booster.
  9. If the vehicle has ABS, remove the master cylinder with the proportioning valve from the brake booster.

  10. If the vehicle has ABS, separate the proportioning valve from the master cylinder. Refer to Proportioning Valve Replacement .
  11. Disassemble, inspect, and reassemble the master cylinder, if necessary. Refer to Master Cylinder Overhaul .

Installation Procedure

  1. Adjust the booster piston rod. Refer to the Adjustment Procedure in Power Vacuum Brake Booster Replacement .
  2. Bench bleed the master cylinder. Refer to Master Cylinder Bench Bleeding .
  3. If the vehicle has ABS, install the proportioning valve to the master cylinder. Refer to Proportioning Valve Replacement .
  4. 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.


    Object Number: 470267  Size: SH
  5. Install the master cylinder (5) and the 2 nuts to the brake booster.
  6. Tighten
    Tighten the nuts to 13 N·m (115 lb in).

  7. Connect the brake pipes.
  8. Tighten
    Tighten the flare nuts to 16 N·m (12.0 lb ft).

  9. Install the reservoir. Refer to Master Cylinder Reservoir Replacement .
  10. Connect the reservoir fluid level connector.
  11. Fill the reservoir. Refer to Master Cylinder Reservoir Filling .
  12. Bleed the hydraulic brake system. Refer to Hydraulic Brake System Bleeding .
  13. Inspect the hydraulic brake system for leaks. Refer to Brake System External Leak Inspection .
  14. Inspect the brake pedal travel. Refer to Brake Pedal Travel Measurement and Inspection .
  15. Perform the brake system vehicle road test. Refer to Brake System Vehicle Road Test .