A pre-transmission unit for a hybrid drive system includes an input shaft adapted to be driven by an internal combustion engine. An electric motor includes a rotor fixed for rotation with an output shaft, and a stator fixed to a housing. A multi-plate clutch is positioned in the housing to drivingly interconnect the input shaft and the rotor. The clutch includes a piston for applying an input force to the clutch plates. A pump is positioned in the housing and includes an input member fixed for rotation with the rotor. The pump provides pressurized fluid to the piston. A valve regulates the fluid pressure applied to the piston and varies the torque transferred by the clutch.