Brake Master Cylinder: Service Precautions

CAUTION:
- On ABS equipped vehicles, vacuum in power booster must be pumped down before removing master cylinder to prevent booster from sucking in any contamination. This can be done simply by pumping the brake pedal until a firm pedal is achieved, with the ignition off.

- On vehicles equipped with ABS, the master cylinder is used to create the seal for holding vacuum in the power brake vacuum booster. The vacuum seal in the front of the power brake vacuum booster MUST be replaced whenever the master cylinder is removed from the power brake vacuum booster.

- When replacing the master cylinder on a vehicle equipped with ABS, a NEW vacuum seal MUST be installed in the power brake vacuum booster. Use only the procedure detailed below for installing vacuum seal into power brake vacuum booster. Be sure old vacuum seal is removed from power brake vacuum booster before attempting to install new seal.

- Then lubricating master cylinder push rod, use only Mopar Silicone Dielectric Compound. Using any other type of grease or lubricant on the push rod, will not provide adequate long term lubrication of the push rod.

- If vehicle is equipped with ABS, be sure old vacuum seal is removed from power brake vacuum booster before attempting to install master cylinder and NEW vacuum seal. If vacuum seal is not removed, refer to Removal.