GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 2003 🢒 LeSabre 🢒 Brakes 🢒 Hydraulic Brakes 🢒 Power Vacuum Brake Booster Replacement

Removal Procedure

    Object Number: 678819 Size: SH
  1. Remove the fuel injector sight shield. Refer to Fuel Injector Sight Shield Replacement in Engine Mechanical.
  2. Remove the accelerator control cable and position the cable out of the way. Refer to Accelerator Control Cable Replacement in Engine Controls.
  3. Remove the accelerator control cable bracket and position the cables out of the way. Refer to Accelerator Control Cable Replacement in Engine Controls.
  4. Remove the cruise control module (1) and position out of the way. Refer to Cruise Control Module Replacement in Cruise Control.

    5. Object Number: 707318 Size: SH
  5. Disconnect the electrical connector from the EGR valve (1).
  6. Disconnect the engine harness clips (3).
  7. Position the wiring harness (2) out of the way.

    8. Object Number: 675866 Size: SH
  8. Disconnect the brake fluid level sensor wire connector (1).

    9. Object Number: 420706 Size: SH
  9. Remove the master cylinder attaching nuts.
  10. Remove the master cylinder from the vacuum brake booster. Carefully set the master cylinder aside.
  11. Remove the vacuum brake booster check valve from the vacuum brake booster.
  12. Remove the left insulator panel. Refer to Instrument Panel Insulator Panel Replacement - Left Side in Instrument Panel, Gages, and Console.
  13. Remove the left knee bolster bracket. Refer to Knee Bolster Bracket Replacement in Instrument Panel, Gages, and Console.
  14. Remove the steering column support mounting nuts. Refer to Steering Column Replacement in Steering Wheel and Column.
  15. Lower the steering column and support the steering column with mechanical wire.
  16. Disconnect the stop lamp/ABS/shift lock switch from the brake pedal assembly. Refer to Stop Lamp Switch Replacement in Lighting Systems.
  17. Disconnect the TCC/cruise control release switch from the brake pedal assembly. Refer to Torque Converter Clutch/Cruise Control Release Switch Replacement in Automatic Transaxle - 4T65-E.

    18. Object Number: 695567 Size: SH
  18. Remove the vacuum brake booster pushrod retainer clip (3).
  19. Remove the vacuum brake booster foam spacer (2).
  20. Remove the vacuum brake booster pushrod (1) from the brake pedal.

    21. Object Number: 695564 Size: SH
  21. Remove the vacuum booster attaching nuts (1) from the brake pedal assembly.

    22. Object Number: 106322 Size: SH
  22. Remove the vacuum brake booster from the vehicle.
  23. Remove the vacuum brake booster mounting gasket, if gasket replacement us necessary.

Installation Procedure
  1. Install the vacuum brake booster mounting gasket to booster, if removed previously.

    2. Object Number: 106322 Size: SH
  2. Install the booster to the vehicle.

    3. Object Number: 695567 Size: SH
  3. Connect the vacuum brake booster pushrod (1) to the brake pedal clevis pin.
  4. Connect the vacuum brake booster pushrod foam spacer (2) to the brake pedal clevis pin.
  5. Install the vacuum brake booster pushrod retainer clip (3) to the brake pedal clevis pin.

    6. Object Number: 695564 Size: SH

    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.

  6. Install the booster attaching nuts (1) onto the booster studs.

    7. Tighten
    Tighten the brake pedal to booster stud nuts to 23 N·m (17 lb ft).

  7. Connect the TCC/cruise control release switch to the brake pedal assembly. Refer to Torque Converter Clutch/Cruise Control Release Switch Replacement in Automatic Transaxle - 4T65-E.
  8. Connect the stop lamp/ABS/shift lock switch to the brake pedal assembly. Refer to Stop Lamp Switch Replacement in Lighting Systems.

    9. Object Number: 420706 Size: SH
  9. Install the master cylinder onto the booster. Refer to Master Cylinder Replacement .
  10. Install the steering column. Refer to Steering Column Replacement in Steering Wheel and Column.
  11. Install the left knee bolster bracket . Refer to Knee Bolster Bracket Replacement in Instrument Panel, Gages, and Console.
  12. Install the left insulator panel. Refer to Instrument Panel Insulator Panel Replacement - Left Side in Instrument Panel, Gages, and Console.
  13. Install the vacuum booster check valve to the vacuum booster.

    14. Object Number: 675866 Size: SH
  14. Connect the brake fluid level sensor wire connector (1).

    15. Object Number: 678819 Size: SH
  15. Connect the cruise control module (1). Refer to Cruise Control Module Replacement in Cruise Control.
  16. Install the accelerator control cable bracket. Refer to Accelerator Control Cable Replacement in Engine Controls.
  17. Install the accelerator control cable. Refer to Accelerator Control Cable Replacement in Engine Controls.

    18. Object Number: 707318 Size: SH
  18. Connect the electrical connector to the EGR valve (1).
  19. Connect the engine harness clips (3).
  20. Install the fuel injector sight shield. Refer to Fuel Injector Sight Shield Replacement in Engine Mechanical.