F 350 2WD Pickup V8-7.3L DSL (1988)
Hydraulic Brake Booster: Description and Operation
Fig. 1 Bendix Hydra-Boost Brake Booster
This brake booster is a hydraulically operated booster, receiving its power from the power steering system, Fig. 1. The power steering pump provides
fluid pressure to operate both the brake booster and the power steering gear. This fluid pressure provides a variable power assist that is regulated by
brake pedal application pressure.
The hydro-boost also has a reserve system (compressed gas accumulator) that is designed to store sufficient fluid under pressure to provide at least two
brake applications in the event that fluid flow from the power steering pump is not available. Brakes can also be applied manually if reserve system is
depleted.