rhkwon

I'm looking at some 87 S4's with automatic transmissions. A couple that I have inquired about, the seller says that it's leaking but he does'nt know exactly where from the transmission.

What or where are the sources of leakage that occurs? Is this difficult to fix? Expensive?

Thanks

Bill51sdr

I had one leak at the point where the Bowden cable entered the transmission. The o-ring was missing.

They are also known to leak at the torque converter seals & cooler lines.

I'm sure others will chime in.

rhkwon

Does replacement of the seals entail dropping the transmission?

Mrmerlin

there are also failed pan gasket seals and the o ring seal for the fluid tank as well as the tank cap.
If you have a leaking trans then you have to narrow things down.
Cooler lines will usually begin leaking if they are original, this can be noticed by drips from the trans around the pan area also look at the cats on PS if there is wetness from the lines here the car should not be driven till new cooler lines are fitted as a cat fire can result.
If the trans is dripping from the grate then it indicates the Radial seal and or the front pump O ring seal has failed

rhkwon

So without knowing for sure where it is leaking, it could be an easy fix to something very complicated?

928Myles

Mine leaked from the o-ring around the pump or B valve cover - a simple & cheap replacement with the trans in the car (once I tracked down a part).

Myles

the flyin' scotsman

Yes but there's some simple tests that can be done to determine where the possible leak is from. I'd start by driving the car and assesing how the tranny shift in all forward gears and reverse. Pay attention to how hard and how fast it shifts.

If possible I'd get the car in the air and clean with brake cleaner around the tranny oil reservoir. With the car runing look carefully at the res. cap, the res. pipe to the tranny pan, the res. vent hose and the tranny pan itself. I'd also pay attention to the tranny drain plug and the torque convertor drain; both have a crush washer that can leak. If any of these points are leaking they're all relatively easy to repair.

After that it can become tricky.

JG928S4

Tranny line leaks, once you replace one, look for the others to start leaking, they are not cheap....

auzivision

My 87 S4 auto has been leaking for years (over 5 of ownership). Found out it was leaking when I bought it, and from the looks of it… probably had for some time before.

It was never a lot and always out the TC grate. Was quoted big bucks (over $1K) to fix and decided I was going to take this on myself when I heard about Tran-X.

I had tried some Lucas and Gunk in the past and they didn’t do anything. About 4 months ago, I completed a pan drop, filter, gasket R&R. Now my garage floor is bone dry.

Don’t know how long this will last, but I’m not dropping the rear suspension/ tranny until I have to. I did pick up a decent tranny jack so I have all the tools required when the need arises.

Bottom line, you need to understand how much and where it is leaking to really make an assessment. Could be simple or could require a lot of work (or bucks) to fix.

Following are a few pictures to show you where and how much mine was leaking.

auzivision

Ignore that arrow in the last picture, that was to help another guy locate the reservoir, recycled an old picture.

Mrmerlin

Auzi I would also check the fluid lines pay attention to the ones over the cats, if any are weeping then the lines should be removed and have new hoses crimped on, also have the hose shop install the silicone heat sheathing on the lines

auzivision

Thanks, I plan on doing that this fall when I drop the exhaust to check the end play in my flexplate... don't need any more toasted sharks!

Dan87951

+1