The hydraulic pump in the P72 chassis is a vane-type pump. The fluid reservoirs are separate from the pumps.

There are two bore openings at the rear of the pump housing. The larger opening contains the cam ring, pressure plate, thrust plate, rotor and vane assembly and the end plate, flow control valve and spring. The flow control orifice is part of the pressure line union. The pressure relief valve limits the pump pressure.

The P92 chassis uses a gear-type pump. The fluid reservoirs are separate from the pumps.

The pump used on the P92 chassis has a cartridge type flow divider which passes a regulated amount of flow to a primary port. Excess flow is sent to a secondary port where it is directed to external circuits such as the hydrostatic cooling fan motor. The primary circuit is protected by a factory-set pressure relief valve.