I just did a A4 to M6 swap and I can't seem to get the rear seal (tail shaft) to stop leaking. The first seal leaked like crazy. The seal that I replaced it with only leaks when the car is hammered on. The transmission had all the bearings replaced, along with the main shaft. The torque arm is kind of loose (not bad). I'm trying to figure out why I can't get the rear seal to seal. Any suggestions?

 

Anybody have any suggestions? I guess I can just keep throwing seals at it until one works. Is there a difference between the manual and automatic driveshafts? It seemed to fit pretty tight. I'm out of ideas. I also transferred my automatic ES tranny mount the the manual. They looked the same, but I didn't ever check part numbers. I'm not sure what year T56 it is, would that make a difference?

 

I had to replace two before I finally got it right. There's a bunch of reasons why it could be leaking, one of the most common being that you damaged it while inserting the driveshaft (me, the first time) and also not getting it properly seated and lubing it with tranny fluid to help it slide in (me, second time). Get the right sized drift and take you time making sure it's properly flush before you go to tap it home. I ended up using something with the same diameter as a spray paint can top.

There might also be too much fluid in there (my excuse for why it leake dthe second time since I could have swore I seated it right ) I'm not too sure on it, but I'm not sure if it can hold back an overfill condition. Check your level first, just for the hell of it It's free.

 

I appreciate the reply. I filled the transmission from the top (shifter opening) until it leaked out of the fill plug. Plus, it has leaked enough to where it would be impossible to be overfull, but I'll check it anyway. I really just took the last one and threw it in there. I used a small hammer and got the seal started all the way around and then I tried tapping it in evenly. I did this with the true duals in place, but maybe I should take them down this time and do it right. So, lube it with the tranny fluid and carefully slide the driveshaft in? I'll give this a try this week.

 

Yeah, that's the part that was stressed by the company that re-built my tranny. I guess they had some guy that had to do it like 5 or 6 times because he kept knicking the walls of the seal with the driveshaft.

It's not surgery or anything, just make sure that it's all lined up before you push it in.