The power rack and pinion steering gear has a rotary control valve. The rotary control valve directs hydraulic fluid coming from the hydraulic pump to one side or the other side of the rack piston. The integral rack piston is attached to the rack. The integral rack piston converts hydraulic pressure to a linear force. This linear force moves the rack to one of the following directions:

The force is transmitted through the following components to the steering knuckles:

If hydraulic assist is not available, manual control is still possible. Manual control requires more steering effort. Without hydraulic assist, the movement of the steering wheel transfers to the pinion. The pinion's movement then transfers through the pinion teeth. The pinion teeth mesh with the teeth on the rack. This causes the rack to move.