Saginaw Rack & Pinion Power Steering Gear

DESCRIPTION
This power steering gear assembly incorporates an integral tube and housing, containing a pinion shaft and steering rack. The tube and housing are joined by a plastic injection-bonding process. The pinion shaft is supported in the housing by thrust bearings and bushings. A bushing and bulkhead assembly supports the steering in the tube.

OPERATION
MODELS LESS SPEED SENSITIVE STEERING (SSS)
A rotary-type valve body is used to control the hydraulic steering assist. Fluid under pressure is directed to the gear housing and into the valve body. The valve body then directs fluid to the power cylinder.

A spool valve, connected to the stub shaft by a locating pin, rotates within the valve body. Fluid directional passages, machined into the spool valve, are aligned with fluid passages in the valve body as the spool valve rotates. Fluid is directed through these passages, into either side of the power cylinder through the externally mounted oil lines.

MODELS W/SPEED SENSITIVE STEERING (SSS)
Many late model vehicles use the Magnasteer power steering system. This system uses a standard rack and pinion power steering gear, pump and magnetic rotary valve actuator, located in the steering gear. The actuator varies the level of hydraulic assist according to vehicle wheel speed. Steering assist is increased at lower wheel speeds to help in vehicle parking maneuvering and decreased at higher speeds to enhance road feel.