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For 1990-2009 cars only

Power Vacuum Brake Booster Replacement 3.6L LY7

Removal Procedure

  1. Lift the coolant reservoir up and away from the left front cross brace.
  2. Remove the left front cross brace. Refer to Front End Sheet Metal Diagonal Brace Replacement - Left Side in Body Front End.
  3. Remove the engine control module (ECM) cover from the air cleaner housing.
  4. Remove the ECM and set aside. It is not necessary to disconnect electrical. Refer to Engine Control Module Replacement in Engine Controls - 3.6L (LY7).
  5. Remove the air cleaner and the duct. Refer to Air Cleaner Assembly Replacement in Engine Controls - 3.6L (LY7).
  6. Remove the fuel line retaining bolt from the intake manifold.
  7. Disconnect the fluid level sensor switch from the brake master cylinder.
  8. Disconnect the brake lines from the master cylinder and remove the master cylinder. Refer to Master Cylinder Replacement .
  9. Remove the vacuum hose from the vacuum check valve. Reposition the vacuum hose.
  10. Remove the ABS module and bracket . Refer to Brake Pressure Modulator Valve Replacement in Antilock Brake System.
  11. Install the engine support fixture. Refer to Engine Support Fixture in Engine Mechanical - 3.6L (LY7).
  12. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  13. Remove the left front tire and wheel assembly. Refer to Tire and Wheel Removal and Installation in Tires and Wheels.

  14. Object Number: 621343  Size: SH
  15. Remove the left front fender liner.
  16. Remove the left ball joint from the steering knuckle. Refer to Lower Control Arm Replacement in Front Suspension.

  17. Object Number: 623048  Size: SH
  18. Remove the stabilizer bar links. Refer to Stabilizer Shaft Link Replacement in Front Suspension.
  19. Remove the steering gear mounting bolts.

  20. Object Number: 478740  Size: SH
  21. Remove the 2 left side frame to body bolts.
  22. Important: DO NOT remove the frame to body bolts on the right side.

  23. Loosen, but do not remove, the right frame to body bolts.
  24. Position an oil drain pan under the transmission.
  25. Important: Insure that all pipes, hoses, and wires are clear and not being bound or stressed when lowering the frame.

  26. Lower the vehicle.
  27. Using the engine support fixture, lower the powertrain.
  28. Remove the transmission filler tube. Refer to Transmission Fluid Filler Tube Replacement in Automatic Transaxle - 4T65-E.
  29. Disconnect the fuel pipe retainer from the wheelhouse stud.

  30. Object Number: 180291  Size: SH

    Notice: When disconnecting the pushrod from the brake pedal, the brake pedal must be held stationary or damage to the brake switch may result.

  31. Remove the booster push rod retaining clip and washer (2) from the brake pedal assembly.
  32. Remove the brake booster push rod (2) from the brake pedal (1).

  33. Object Number: 180993  Size: SH
  34. Remove the brake booster mounting nuts.
  35. Remove the brake booster.

Installation Procedure

Caution: When replacing the power booster brake, make sure that the cruise control cable is not routed between the booster and the cowl. If the cable is damaged or pinched, it must be replaced. Failure to do this could result in personal injury.

Notice: Proper stoplamp switch adjustment is essential. Improper stoplamp switch adjustment may cause brake drag, heat buildup and excessive brake lining wear.


    Object Number: 180993  Size: SH
  1. Install the brake booster and position to the cowl and the mounting plate.
  2. Notice: Refer to Fastener Notice in the Preface section.

  3. Install the brake booster mounting nuts.
  4. Tighten
    Tighten the brake booster mounting nuts to 25 N·m (18 lb ft).


    Object Number: 180291  Size: SH
  5. Install the brake booster push rod (2) to the brake pedal (1).
  6. Install the brake booster rod retaining washer and clip to the brake pedal assembly.
  7. Adjust the stop lamp switch. Refer to Stop Lamp Switch Adjustment in Lighting Systems.
  8. Connect the fuel pipe retainer to the wheelhouse stud.
  9. Install the transmission filler tube. Refer to Transmission Fluid Filler Tube Replacement in Automatic Transaxle - 4T65-E.
  10. Using the engine support fixture, raise the powertrain to its original position.
  11. Raise the vehicle.
  12. Using an appropriate jack, raise the left side of the frame so that the frame to body bolts can be installed.

  13. Object Number: 478740  Size: SH
  14. Install the frame to body bolts.
  15. Tighten

        • Tighten the front bolts to 155 N·m (114 lb ft).
        • Tighten the rear bolts to 240 N·m (177 lb ft).
  16. Remove the jackstand and oil drain pan.
  17. Install the steering gear mounting bolts.
  18. Tighten
    Tighten the bolts to 80 N·m (59 lb ft).


    Object Number: 623048  Size: SH
  19. Install the stabilizer bar links. Refer to Stabilizer Shaft Link Replacement in Front Suspension.
  20. Install the ball joint to the steering knuckle. Refer to Lower Control Arm Replacement in Front Suspension.

  21. Object Number: 621343  Size: SH
  22. Install the left front fender liner.
  23. Install the left front tire and wheel assembly. Refer to Tire and Wheel Removal and Installation in Tires and Wheels.
  24. Lower the vehicle.
  25. Remove the engine support fixture.
  26. Install ABS module bracket and module. Refer to Brake Pressure Modulator Valve Replacement in Antilock Brake System.
  27. Install the vacuum hose to the check valve.
  28. Install the brake master cylinder and connect the brake lines . Refer to Master Cylinder Replacement .
  29. Connect fluid level sensor switch on the master cylinder.
  30. Install the fuel line retaining bolt to the intake manifold.
  31. Tighten
    Tighten the bolt to 10 N·m (89 lb in).

  32. Install the air cleaner and duct assembly. Refer to Air Cleaner Assembly Replacement in Engine Controls - 3.6L (LY7).
  33. Install the ECM . Refer to Engine Control Module Replacement in Engine Controls - 3.6L (LY7).
  34. Install the ECM cover.
  35. Install the left front cross brace . Refer to Front End Sheet Metal Diagonal Brace Replacement - Left Side in Body Front End.
  36. Reposition the coolant reservoir to the left front cross brace.
  37. Bleed the brake system. Refer to Hydraulic Brake System Bleeding .

Power Vacuum Brake Booster Replacement 3.5L

Removal Procedure

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.

  1. Relieve fuel line pressure. Refer to Fuel Pressure Relief for the 3.5L engine.
  2. Drain the cooling system. Refer to Cooling System Draining and Filling .
  3. Remove the coolant reservoir. Refer to Coolant Recovery Reservoir Replacement .
  4. Remove the left front cross brace. Refer to Front End Sheet Metal Diagonal Brace Replacement - Left Side .
  5. Remove the powertrain control module (PCM) cover from the air cleaner housing.
  6. Remove the PCM and set aside. It is not necessary to disconnect the electrical connector. Refer to Powertrain Control Module Replacement for the 3.5L engine.
  7. Remove the air cleaner and the duct. Refer to Air Cleaner Outlet Duct Replacement for the 3.5L engine.
  8. Remove the fuel lines from the pipes and vapor line.
  9. • For vehicles equipped with metal connectors, refer to Metal Collar Quick Connect Fitting Service .
    • For vehicles equipped with plastic connectors, refer to Plastic Collar Quick Connect Fitting Service .
  10. Remove the heater hose from the coolant cross over pipe and reposition out of the way. Refer to Heater Pipes Replacement .
  11. Unclip the fuel lines from the shock tower for easier access to the brake pipes.
  12. Disconnect the fluid level sensor switch from the brake master cylinder.
  13. Disconnect the brake lines from the master cylinder and remove the master cylinder. Refer to Master Cylinder Replacement .
  14. Remove the ABS module and bracket. Refer to Brake Pressure Modulator Valve Replacement .

  15. Object Number: 177473  Size: SH
  16. Remove the brake booster vacuum hose from the vacuum brake booster check valve. Reposition the vacuum hose.
  17. Remove the knee bolster. Refer to Knee Bolster Replacement .

  18. Object Number: 180291  Size: SH
  19. Remove the booster push pin retaining clip and washer (2) from the brake pedal assembly.
  20. Remove the brake booster push rod (2) from the brake pedal (1).

  21. Object Number: 180993  Size: SH
  22. Remove the brake booster mounting nuts.
  23. Remove the 2 front engine mounts, nuts, and bolts. Refer to Engine Mount Strut Replacement - Left Side and Engine Mount Strut Replacement - Right Side for the 3.5L engine.
  24. Rotate the engine forward to gain access to the brake booster removal. Refer to Rotating the Engine for Service Access for the 3.5L engine.
  25. Remove the brake booster.

Installation Procedure

Caution: When replacing the power booster brake, make sure that the cruise control cable is not routed between the booster and the cowl. If the cable is damaged or pinched, it must be replaced. Failure to do this could result in personal injury.


    Object Number: 180993  Size: SH
  1. Position the brake booster to the cowl and the mounting plate.
  2. Notice: Refer to Fastener Notice in the Preface section.

  3. Install the brake booster mounting nuts.
  4. Tighten
    Tighten the brake booster mounting nuts to 25 N·m (18 lb ft).

  5. Install the master cylinder. Refer to Master Cylinder Replacement .

  6. Object Number: 180291  Size: SH
  7. Install the brake booster push rod (2) to the brake pedal (1). Install the washer and retaining clip.
  8. Notice: Proper stoplamp switch adjustment is essential. Improper stoplamp switch adjustment may cause brake drag, heat buildup and excessive brake lining wear.

  9. Adjust the stoplamp switch. Refer to Stop Lamp Switch Adjustment .
  10. Install the knee bolster. Refer to Knee Bolster Replacement .
  11. Rotate the engine back and install the engine mounts, bolts, and nuts. Refer to Rotating the Engine for Service Access for the 3.5L engine.

  12. Object Number: 177473  Size: SH
  13. Install the brake booster vacuum hose to the vacuum brake booster check valve.
  14. Install the ABS module bracket and module. Refer to Brake Pressure Modulator Valve Replacement .
  15. Install the brake master cylinder and connect the brake lines. Refer to Master Cylinder Replacement .
  16. Connect the fluid level sensor switch on the master cylinder.
  17. Install the fuel pipes to the pipes shock tower.
  18. Install the heater hose to the coolant cross over pipe. Refer to Heater Pipes Replacement .
  19. Install the air cleaner and duct. Refer to Air Cleaner Outlet Duct Replacement for the 3.5L engine.
  20. Install the PCM. Refer to Powertrain Control Module Replacement for the 3.5L engine.
  21. Install the PCM cover.
  22. Install the left front cross brace. Refer Front End Sheet Metal Diagonal Brace Replacement - Left Side .
  23. Install the coolant reservoir. Refer to Coolant Recovery Reservoir Replacement .
  24. Fill and bleed the cooling system. Refer to Cooling System Draining and Filling .
  25. Bleed the brake system. Refer to Hydraulic Brake System Bleeding .