ATF Leaking Bad

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REman
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ATF Leaking Bad

Post by REman »

Hey Guys,

Any ideas what this ATF leak fix might be? I cleaned up the housing where it meets the engine and this was the obvious (pics
ATF Leak.jpg
) location.

Did some digging in the repair manual and only suggestion I found was the "shaft seal"? No idea where that might be or how to replace if the culprit.

Thanks as always for any help/suggestions

Ivan
Attachments
ATF Leak 2.jpg
'81 528i... mfg date 10/80...owned since 1990
HB528i
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Re: ATF Leaking Bad

Post by HB528i »

I had a leak that I was sure was coming from the rear main seal or input shaft of the trans. It turned out to be the oil pressure sending unit, not the seal though, it was leaking from the plastic housing itself and sends quite a bit of oil down the side of the block to the bell housing. Worth a look.
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REman
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Re: ATF Leaking Bad

Post by REman »

That would be engine oil then, this is for sure ATF. Thanks.
'81 528i... mfg date 10/80...owned since 1990
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Mike W.
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Re: ATF Leaking Bad

Post by Mike W. »

Oil leaks like that you just have to clean them up then keep a close eye on where they start leaking from. Remember the power steering uses ATF too, so it, the related hoses and even the steering box are all suspects. Clean it up, drive it for half an hour and take a look. If not then, check tomorrow. Steering boxes in particular can be tricky, I've had them not leak while driving but leave a dinner plate size puddle overnight.
Mike W.



1980 528i, 3.5 euro, 5 speed conversion
1981 528i, 3.6, Recaros and more. Project
1998 328is, quick and efficient, but not satisfying
2000 528iit, Vacation mobile/wife's grocery getter
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REman
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Re: ATF Leaking Bad

Post by REman »

Thanks Mike! I have done as you suggested and have had to put almost a whole quart of ATF back in the transmission so apparently not the steering components.
'81 528i... mfg date 10/80...owned since 1990
RDAvena
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Re: ATF Leaking Bad

Post by RDAvena »

Its the transmission input shaft seal that is getting ready to go. Mine did the same thing.
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REman
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Re: ATF Leaking Bad

Post by REman »

Thanks, did you have to drop the trans to replace or?
'81 528i... mfg date 10/80...owned since 1990
Schneider
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Re: ATF Leaking Bad

Post by Schneider »

ATF
ATF
Hello

i think the shaft sealing ring of the gearbox is leaking.
prerequisite it is switched or dogleg.
John
John
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REman
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Re: ATF Leaking Bad

Post by REman »

Yes I think you hit it on the nail, thanks John!
'81 528i... mfg date 10/80...owned since 1990
RDAvena
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Re: ATF Leaking Bad

Post by RDAvena »

REman wrote: Mon Apr 05, 2021 6:44 am Thanks, did you have to drop the trans to replace or?
Correct. I did drop/replace the transmission. Once pulled the seal fell out with the torque converter.
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REman
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Re: ATF Leaking Bad

Post by REman »

Haven't had work done yet as I'm not sure who to give the work here in Orlando to, but wanted to get ideas of what else would/should be replaced along the way even though the trans works just fine.

Any suggestions? Ideas welcome.
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Mike W.
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Re: ATF Leaking Bad

Post by Mike W. »

Personally I'd just do a fluid change in addition to changing the seal if the tranny seems to be in good shape otherwise. Given the location it shouldn't require an A/T shop, it's just a seal. The hard part is R and R'ing the tranny not changing the seal.

I would also use new copperlock nuts on the exhaust although don't be surprised if they fight whoever takes the exhaust out, I've found I usually have to resort to a 6 point socket to either remove the nuts or the nuts with the stud that sometimes comes with them.
Mike W.



1980 528i, 3.5 euro, 5 speed conversion
1981 528i, 3.6, Recaros and more. Project
1998 328is, quick and efficient, but not satisfying
2000 528iit, Vacation mobile/wife's grocery getter
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