Transmission pump seal

The present invention provides a seal apparatus for a transmission pump. The seal apparatus includes a ring seal configured to seal a gap defined between a transmission pump body and a hub in order to reduce hydraulic fluid leakage. An O-ring is placed around the ring seal such that the O-ring engages the transmission pump body in an axial direction. A retainer ring is disposed around the hub, and a torque converter seal is disposed radially between the transmission pump body and the hub. The torque converter seal applies an axial force which is transferred through the retainer ring in order to compresses the O-ring against the transmission pump body to seal in parallel with the ring seal such that the rate of hydraulic fluid leaking from the transmission pump is reduced. A corresponding method for sealing a transmission pump is also provided.