I know Mercades (spell) made a auto that could be bump started (push started). It had a pump in the tranny on the output end. I was wondering if anyone knew more on this tranny (Part number)?

I don't know the number but I beleive the trans with the rear pump was available on the Mercs up until the early 70's. I think most early autos had 2 pumps(1 on the input and 1 on the output) but were dropped in the mid 60's. Another example would be a 2 speed Powerglide. If you had a manual lockup on the torque converter it could be possible to push start. I understand it needs 25-35 mph to push start an auto. None of this is gospel, just what I've picked up around the place.