GM Service Manual Online
For 1990-2009 cars only

The constant displacement vane type pump provides hydraulic pressure and flow for the steering system. The pump is belt driven by the power steering pump pulley and crankshaft pulley. The opening at the rear of the pump housing contains:

    • The pump ring
    • The pressure plate
    • The thrust plate
    • The rotor
    • The vanes
    • The end plate

A small opening on the side of the housing contains the pressure line fitting. A pressure relief valve inside the flow control valve limits the pump pressure.