GM Lumina/Grand Prix/Cutlass Supreme/Regal 1988-1996



The power rack and pinion steering system has a rotary control valve which directs hydraulic fluid coming from the steering pump to one side or the other side of the rack piston. The piston converts hydraulic pressure to linear force which moves the rack right or left. When power assist is not available, manual control is maintained; however, more steering effort is needed. A vane type steering pump provides hydraulic pressure for steering assist.