Brake Booster (Vacuum)

WARNING: This page does not describe the selected car, but rather 13 other vehicles, including the 2004 Ford Pickup, 2004 Ford F550 Super Duty, 2004 Ford F450 Super Duty, 2004 Ford Excursion, and 2003 Ford Pickup. However, it is still accessible from the selected car via links, so may be relevant.

Some models are equipped with a dual-diaphragm vacuum booster. Boosters are self-contained, vacuum power brake units. Booster assists in actuating master cylinder push rod. See Figure.

The vacuum type power brake booster is a dual diaphragm, vacuum assisted power brake booster which reduces brake pedal force and travel distance. The vacuum booster is located on the left side of the bulkhead in the engine compartment, between the brake pedal and the brake master cylinder. The booster is divided into separate chambers by the diaphragms. The booster will not operate if vacuum is restricted or if any of the vacuum related power brake components fail. The booster is installed as an assembly. If the power assist fails, the brake system will continue to operate with increased brake pedal effort.