518 transmission

I have a 1996 dodge full size van with a a518 tranny. The tranny has been completely rebuilt 3 times in the last month literally. My tranny guy cant figure it out. Keeps burning up the overdrive section causeing failure etc. He mentioned to me that the manual says to block off the lube tubes in the pump because this tranny doesnt use the tubes. Well the rear end is burning up all the time lack of lube. Should we unblock the holes or is there another issue that we arent see?