GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 1999 🢒 GMC K Sierra - 4WD 🢒 Brakes 🢒 Hydraulic Brakes 🢒 Power Vacuum Brake Booster Replacement

Removal Procedure

    Caution: Unless directed otherwise, the ignition and start switch must be in the OFF or LOCK position, and all electrical loads must be OFF before servicing any electrical component. Disconnect the negative battery cable to prevent an electrical spark should a tool or equipment come in contact with an exposed electrical terminal. Failure to follow these precautions may result in personal injury and/or damage to the vehicle or its components.

  1. Disconnect the negative battery cable.
  2. Apply the parking brake.
  3. Disable the SIR. Refer to Disabling the SIR System .

    4. Object Number: 344196 Size: SH
  4. Remove the brake master cylinder. Refer to Master Cylinder Replacement .
  5. Remove the vacuum hose at the booster.

    6. Object Number: 344194 Size: SH
  6. Disconnect the electrical connection from the stoplamp switch.

    7. Remove the pushrod retaining clip (4).

  7. Remove the stoplamp switch (2).
  8. Remove the pushrod (3) from the brake pedal stud (1).

    9. Object Number: 344197 Size: SH
  9. Remove the vacuum booster mounting nuts.
  10. Remove the vacuum booster.
  11. Remove the gasket from the booster and discard.

Installation Procedure

    Object Number: 344197 Size: SH
  1. Install the gasket to the booster
  2. Install the vacuum 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.

  3. Install the vacuum booster mounting nuts.

    4. Tighten
    Tighten the nuts to 36 N·m (27 lb ft).


    Object Number: 344194 Size: SH
  4. Install the pushrod (3) to the brake pedal stud (1).
  5. Install the stoplamp switch (2).
  6. Connect the electrical connection to the stop lamp switch.
  7. Install the vacuum hose at the booster.

    8. Object Number: 344196 Size: SH
  8. Install the master cylinder.

    9. Refer to Master Cylinder Replacement .

  9. Connect the negative battery cable.
  10. Release the parking brake.
  11. Enable the SIR. Refer to Enabling the SIR System .