GM Service Manual Online
For 1990-2009 cars only

Master Cylinder Replacement Vacuum Boost

Removal Procedure

  1. Apply the parking brake.
  2. Disconnect the electrical connection at the brake fluid level sensor

  3. Object Number: 493214  Size: SH
  4. Disconnect the brake pipes.
  5. Plug the pipes in order to prevent brake fluid loss or contamination.

  6. Object Number: 344196  Size: SH
  7. Remove the master cylinder mounting nuts.
  8. Remove the master cylinder.

Installation Procedure

Before you install the master cylinder, bench bleed the master cylinder. Refer to Master Cylinder Bench Bleeding .


    Object Number: 344196  Size: SH
  1. Install the master cylinder
  2. 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.

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

  5. Remove the pipe caps.

  6. Object Number: 493214  Size: SH
  7. Connect the brake pipes.
  8. Tighten
    Tighten the fittings to 25 N·m (18 lb ft).

  9. Connect the electrical connection at the brake fluid level sensor.
  10. Bleed the brakes. Refer to Antilock Brake System Automated Bleed Procedure
  11. in Antilock Brake Systems.

  12. Release the parking brake.

Master Cylinder Replacement Hydraulic Boost

Removal Procedure

  1. Apply the parking brake.

  2. Object Number: 375694  Size: SH
  3. Disconnect the electrical connection at the brake fluid level sensor
  4. Disconnect the brake pipes.
  5. Plug the pipes in order to prevent brake fluid loss or contamination.
  6. Remove the master cylinder mounting nuts.
  7. Remove the master cylinder.

Installation Procedure

Before you install the master cylinder, bench bleed the master cylinder. Refer to Master Cylinder Bench Bleeding .


    Object Number: 375694  Size: SH
  1. Install the master cylinder.
  2. 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.

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

  5. Remove the pipe caps.
  6. Connect the brake pipes.
  7. Tighten
    Tighten the pipe fittings to 25 N·m (18 lb ft).

  8. Connect the electrical connection at the brake fluid level sensor.
  9. Bleed the brakes. Refer to Antilock Brake System Automated Bleed Procedure
  10. in Antilock Brake Systems.

  11. Release the parking brake.