Brake Booster - Hydro-Boost (Description and Operation)

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 Section to check the power steering pump pressure and flow.

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

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