F 550 4WD Super Duty V10-6.8L VIN D (2004)
Hydraulic Brake Booster: Description and Operation
DESCRIPTION AND OPERATION
Brake Booster-Hydro-Boost
The Hydro-Boost brake booster is a hydraulically operated brake booster powered by the power steering pump. The power steering pump provides the
fluid pressure to operate both the power brake booster and the power steering gear.
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, check power steering pump pressure and flow. Refer to: Steering / Testing
and Inspection, See: Steering and Suspension/Steering/Testing and Inspection/Component Tests and General Diagnostics
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.
