Hydraulic Brake Booster: Service and Repair

Brake Booster - Hydro-Boost(R)

















Removal and Installation

WARNING: Always carry the Hydro-Boost(R) assembly by the casting. The accumulator contains high-pressure nitrogen gas and may be dangerous if dropped or impacted. Check the accumulator snap ring for correct seating prior to installation. Failure to follow these instructions may result in serious personal injury.

WARNING: When disposing of the accumulator, do not expose it to incineration or open flame. Before discarding the accumulator, drill a 1.6 mm (0.06 in) diameter hole in the end of the accumulator can to relieve gas pressure. Failure to follow these instructions may result in serious personal injury.

1. With the engine off, apply the brake pedal several times to deplete the brake booster accumulator reserve.

2. NOTICE: Do not activate the brake booster with the brake master cylinder removed or damage to the booster may occur.

Remove the brake master cylinder. Refer to Hydraulic Brake Actuation Brake Master Cylinder.

3. Disconnect the power steering pressure line fittings.
- Remove and discard Teflon(R) seals.

- To install, tighten to 63 Nm (46 lb-ft).

4. Using the Teflon(R) Seal Installer Set, install new Teflon(R) seals on the power steering pressure fittings.





5. Disconnect the power steering fluid return hose.





6. NOTICE: Do not service the brake pedal or brake booster without first removing the stoplamp switch. This switch must be removed with the brake pedal in the at-rest position. The switch plunger must be compressed for the switch to rotate in the bracket. Attempting to remove the switch when the plunger is extended (during pedal apply) will result in damage to the switch.

Remove the stoplamp switch. For additional information, refer to Exterior Lighting Service and Repair.

7. Disconnect the brake booster push rod in the following sequence.

1. Remove the brake booster push rod cotter pin cover.

2. Remove the brake booster push rod cotter pin.

3. Remove the spacer.

4. Disconnect the brake booster push rod from the brake pedal pin.

8. Remove the 4 brake booster nuts and the brake booster.
- To install, tighten to 25 Nm (18 lb-ft).

9. NOTICE: Do not press, pull or otherwise move the brake pedal while installing the stoplamp switch. This switch must be installed with the booster push rod attached to the brake pedal and with the brake pedal in the at-rest position. Installing this switch with the brake pedal in any other position will result in incorrect adjustment and may damage the switch.

To install, reverse the removal procedure.

- Fill the power steering fluid reservoir. For additional information, refer to Steering System Power Steering System Filling.