Control in "assist" position

Control in "assist" position

A Edge of the pinion holder

4-way valve moves back to neutral position

Full-Lock Unloader System

The 4-way valve shifts the direction of fluid flow when the steering wheel is turned, right or left. However, when the wheel is turned to the right or left lock at parking speed, the edge of the pinion holder rides up on the end of the rack, moving the pin in the opposite direction which pulls the 4-way valve back to neutral.

This keeps pump pressure from building up (which could cause idle speed to drop), and improves steering feel by increasing resistance at left and right lock.

Power Steering Speed Sensor

A Inner Rotor

B Outer Rotor

C Relief Valve

D One-way Valve

E Speedometer Gear

The power steering speed sensor is a trochoid-rotor, hydraulic pump combined with a relief valve and a one-way valve. It is driven by the speedometer gear shaft which in turn is driven by a helical gear on the differential.