Brake Booster - Hydro-Boost

WARNING: This page is about a different car, the 2003 Ford Pickup, 2003 Ford F550 Super Duty, 2003 Ford F450 Super Duty, 2003 Ford Excursion, and 2003 Ford Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.

The Hydro-Boost brake booster is a hydraulically operated brake booster powered by the power steering pump (3A674). The power steering pump provides the fluid pressure to operate both the power brake booster and the power steering gear (3504).

A Hydro-Boost reserve system (accumulator) stores sufficient fluid under pressure to provide at least two power-assisted brake applications in the event the power steering pump fluid flow is interrupted.

For low assist concerns on vehicles equipped with the Hydro-Boost system, refer to STEERING SYSTEM-GENERAL INFORMATION to check the power steering pump pressure and flow.

Fig 1: Identifying Brake Booster - Hydro-Boost

Courtesy of FORD MOTOR CO.

The brakes can also be applied manually if the reserve system is depleted.

Model identification is stamped into the power brake booster housing near the power steering pressure hose.

Any leakage goes directly back to the power steering pump reservoir (3E764).