ZF transmisson input shaft seal leaking

[surebimmer]

Well I got my S52 swap track 88 M3 car done for bimmerfest. Made the drive down to SB and back about 450 miles round trip. I noticed i had a leak of oil from the bell housing area. Well i pulled the transmission today and sure enough the transmission is leaking from the input shaft seal that i replaced before i put the transmission in and did the swap. So the spent today replacing the input shaft seal again and went and drove around about 50 miles with a new OEM dealer input shaft seal and it's leaking worse then the last one. Anyone got any idea's?

[416stroker]

Whats it look like were the seal seats did you score it?

[surebimmer]

I installed the seal with the factory seal install tool. I work at a dealer. So i'm unsure of what your asking.

[416stroker]

Howd you take it out? I dont know how to make it any more clear? Is there any scoring where the seal sits in the trans?

[surebimmer]

With a seal puller. The case is clean with no scores. It seem to be leaking from the inner part of the seal. Were the inner spring and seal part meet the input shaft.

[416stroker]

you clean the shaft up with some emery cloth? Theres no pitting or anything on the shaft.

[surebimmer]

i didn't clean it up. But the shaft is clean no pitting at all.

[416stroker]

Idk then. Has to be something do do with the imput shaft.

[surebimmer]

To much play in the input shaft maybe? There is no noises coming from the trans. Wasn't leaking before i replaced it. But thought it was a good idea to replace it. i guess the saying goes if it ain't broke don't fix it.

[jahnaboi]

Your input shaft could have excessive play which is causing to stress the seal too much on one side causing a slight gap on the opposite side. Iono? All I could think of. Not much really that could go wrong with changing seals so I'm stomp as much as you are.

[jahnaboi]

lol. I laugh that we were both typing our responses at the same time just different by 1 min.

[416stroker]

To much play in the input shaft maybe? There is no noises coming from the trans. Wasn't leaking before i replaced it. But thought it was a good idea to replace it. i guess the saying goes if it ain't broke don't fix it.

Your input shaft could have excessive play which is causing to stress the seal too much on one side causing a slight gap on the opposite side. Iono? All I could think of. Not much really that could go wrong with changing seals so I'm stomp as much as you are.

I agree with bolth of you that could be it. I hope its not. is there any vibrations?

[surebimmer]

No vibrations at all.

[surebimmer]

well if no help maybe a cheap zf is the answer.

[e30serg]

Is there a way you could check the input shaft OD to factory specs? What about the seal ID? Are you lubing the seal before pressing it on (seal/spring side)?