A-904 Pump front seal replacement.

While you're at it, now is the time to also replace the pump gasket, the pump to case seal (large O ring) and the 6 front pump bolt washer/seal. If the front pump seal is replaced it's a good idea to pack it with Vaseline, as this helps prevent the garter spring from coming out. While inspecting the converter hub area, look closely at the welds around the hub. Might be an issue there.
Just a couple of suggestions.