Originally Posted by sbchevfreak
Did the previous work done include bushing replacement ? Or did the guy that did the first job just do the seal?? If he gouged the bushing bad enough, he could have caused enough clearance to cause a leak under heavy load. The pump/converter bushing can have significant pressure behind it, and if the oil has somewhere to go, it will. That seal will only hold so much pressure and volume.
EDIT: I found this on ALLDATA, and it may relate -
From what I was told, the entire bushing was pulled out and thrown away. Then a new seal was installed and the trans put back in...with NO bushing!
I guess he was scared that he trashed the entire trans and was hoping for the best.