So my '96 Z28 has been in winter hibernation storage for over a month now. And it had no issues when I was driving it but I went out to the garage today just to check on it and saw that it is now leaking transmission fluid. I can see the drop coming off of that inspection cover right behind the oil pan. It has left about a fist sized puddle on the ground. What I'm worried about is if it's leaking like that now, I'm worried if it's gonna end up pouring out once I run the car again. This would mean the input seal or pump seal is leaking? I'm definitely bummed because I am really looking forward to getting this car back out In the spring and having some fun with it, but now I may potentially have to drop the transmission and have it rebuilt or something. Could it just be the cool temperatures causing the seals to contract and make it leak? And maybe once it drives again the seal will swell back up and it won't leak as much?

I can live with a little leak, the engine itself leaks a bit of oil too, but if it's going to straight up be hemorageing tranny fluid then obviously I can't live with that. Anyone had any similar experiences with the 4L60E? I'm really hoping it won't be bad because I really want to enjoy this car this spring, and the month I've gone so far without driving it has been terrible and I miss it. Let me know guys, thanks.

 

Our 2005 Trailblazer was doing the same,I found most of the pan bolts weren't tight probably due to the gasket shrinking.
I snugged them all up and no more leaking,I'm selling it or I'd probably get a trans flush and fill service done with a filter and gasket replacement.

 

That would be nice, but since the drop is on the torque converter inspection cover I can't imagine it being the pan. It's gotta be the pump seal, I'm just hoping that the leak will get better once it starts being driven again. I'm praying it's that and that it doesn't start pouring out the next time I start it up.

 

Trans removal should be 4-5 hours and another .5 hours to install the seal. It would be worth it to do if the transmission mileage is not too high. There is a chance the seal scared the converter. If its scared it should be replaced. this is normally just on high miles transmission.

I would guess the seal replacement is between 400-600 bucks. Add 300-500 if you need a converter.

If the transmission leaks worse running then not running then this needs fixed ASAP. If it is leaking a dime size leak every night (it adds up over time) then you just need to maintain the level. and put something under the car and keep an eye on it. The seal can be worn, it can be hard or it can be ripped a small amount. This makes guessing how long it will stay in its current state tuff. A worn seal can last a while. A hard seal can last a while but it is likely to groove the converter and a ripped seal can continue to rip or just have a small chunk out of it and last like it is for a long time.

Careful with the transmission seals in a can (stop leak or rebuild in a can). If your seals is hard it can help, that is what they do "soften seals" but they can also make a tear a lot worse. The makers of that stuff help enough of the people they can say it works but they do not tell you about the transmission they rendered unusable within 48 hours. The only time I would try it is if I had a low miles trans that had been sitting for awhile. I would using knowing what the results could be. You could fix the front seal but cause the 1-2 shift to fail.