328i Automatic transmission leak

[Boonie30]

Hello all, I have a 1998 328i with the automatic transmission and it has a fluid leak at the front of the transmission. Transmission has both pan gaskets scraped off and replaced and still manages to lose fluid. I can drive around town slowly (around 45) no problem but if i get to higher speeds (60 and up) where it heats up there is a tranny fluid mist following me. It drains the fluid and of course makes the tranny slip eventually.

I swapped motors because of a burnt piston and while connected to the old motor there were no tranny leaks, I swapped motors and reattached this transmission and now it leaks.

Any ideas?

[scooper]

you can try putting a very, very thin bead of rtv on the outer edge of the pan gaskets. Let the car sit a few days without turning it on for the rtv to cure. Take care not to put too much because you don't rtv inside the pans. Clean the magnet while you are in there. Did you replace the drain plug aluminum gaskets?

[Eric93se]

You are probably leaking from the trans input shaft seal. You should also replace the input shaft o-ring.

[Boonie30]

you can try putting a very, very thin bead of rtv on the outer edge of the pan gaskets. Let the car sit a few days without turning it on for the rtv to cure. Take care not to put too much because you don't rtv inside the pans. Clean the magnet while you are in there. Did you replace the drain plug aluminum gaskets?

I'll give this a shot thank you

- - - Updated - - -

You are probably leaking from the trans input shaft seal. You should also replace the input shaft o-ring.

Does replacing the seal require removing the transmission entirely?

[shogun]

Does replacing the seal require removing the transmission entirely?

Yes, transmission has to come out and the torque converter.

[Boonie30]

Yes, transmission has to come out and the torque converter.

Thank you so much!

[shogun]

here as example a 4HP22 repair, there you can see the shaft seal http://www.nmia.com/~dgnrg/page_43.htm
The most common leak points on automatic transmissions are the input and output shaft seals.

[jclausen]

Also see if it's coming out the vent at the top of the trans case, if it is trans is done