I went and checked the vehicle out this morning. It's an 85' Sport Coupe w/ 2.8l v6. 140k original miles. The motor is super strong! That being said, I noticed a leak coming from the transmission (auto). It was after I moved the vehicle. It has been parked for 9 months. The owner said it leaks a little transmission fluid when it sits for a bit. It's just a really tiny amount but still concerning. He replaced the pan gasket and filter but it still leaks. Could it be the pump seal? I haven't worked on one of these in years. This will be my first camaro since I was in my dads as a kid in the early 2000s. Any tips would be greatly appreciated. I am newer to the GM scene so any and all info will be great! Thank you!

 

It might be the speedometer cable seal. Might be the rear seal...

 

I've never done a rear seal with an auto trans before, only on manuals. Is it about the same process? The transmission runs great and wasn't grinding or slipping at all, fluid level was normal. I might take it into an AAMCO to get a diag.

 

Could also be the shaft seal. Had to replace that in our 84.

 

Same process, remove the driveshaft, pop the old seal out, put the new seal in, reinstall the driveshaft.

 

Usual trans leak when sitting is, the fill tube seal.

https://www.rockauto.com/en/moreinfo...=23047&jsn=519

Note carefully, the extreme expense.

The level of the fluid inside the trans is higher than the fill tube thing, but goes down to below it when running.

Won't be the drive shaft seal; there's little to no fluid there when sitting.

I strongly recommend AGAINST taking it to Aamco, or to any other transmission shop, for this. Usual recommendation will be to replace the whole transmission. Not exactly the most economic way of dealing with it.

Take the car to the quarter (dollar? credit card?) car wash, along with your floor jack and jack stands, and acoupla cans of engine degreaser (diesel fuel in a spray can). Get up under it and sterilize the whole underside. It's amazing how much easier it is to see a fresh leak on spotlessly clean shiny parts, than to try to dig through 10,000 years of funk all deposited all over everything.

 

Did you get the car

 

With a difficult to locate Fluid leak (like what has been described here)...

I would recommend making a small purchase.
Buy yourself a Can of Brake Parts Cleaner, and tiny Bottle of Automotive Fluid Leak Detector Dye (Florescent or UV Reactive Dye for Oils).

Spray off as much gunk and oil from the areas of the Transmission that are filthy...
Add the Dye into the Transmission via the ATF Dip-Stick/ Filler Tube.

Drive the car a short distance.
Park the Vehicle and let it cool down some before going under/ looking under the Vehicle (do NOT burn yourself)...
Inspect for the Dye to see where the Leak is occurring ...or at the least narrow it down to a general area.