post #11 clearly shows a plug. I'm assuming this is an overdrive trans?
No solvent washing will not work. That's probably what the last guy thought, and it didn't work for him did it? No solvent has it's own oils in it. And like I said, the oil inside the box will want to creep up no matter what. The best and only solution, in my mind, is as earlier described. I hate doing things over and over with the same result, and that tranny is too heavy at my age,lol