Mysterious transmission leak

[jedi]

Here is a good mystery for you Corvette masters. I have another leaking seal, this time it is coming from somewhere in the transmission. Every morning when I go out to the garage I find a small puddle in the middle of my floor. This time it's red, so therefore it must be coming from the transmission. I took the car to a local jiffy lube and had the transmission pan gasket replaced. Then I took the car a few week later to Amoco to have the transmission checked. It seems to slip a bit in 2nd or third (Was doing it before Jiffy) but I suspected the flywheel was slipping on the oil from the old oil leak. Amoco had it over night and they found "A" source of a leak. The speedometer (or something like that) had a seal that was leaking. They replaced that but did not find anything else wrong with the transmission. No codes no nothing, just the occasional slip which they could not reproduce. The slip itself is a little weird no change in rpm just a brief loss of power. Amoco also noticed that the bolts on the transmission pan were not tight and suggested I take it back to Jiffy. The leak continues, Jiffy could not find it, (then even let me down under the car to look) Amoco could not find it. Where could this be coming from? Any suggestions would be very helpful.
Jedi

 

[tnovot]

Do you know if the leakage is from the front, middle, or rear of the trans? That would help to isolate the source.
If it were me, I'd clean the leakage from around the pan, sides of trans, and rear seal. Then I'd let it sit a day or two without starting and then check everywhere visually at first and then with a clean rag or glove to locate the leak.
If no leak is found, do the same checks after driving it for a while.
If still no leak is found, check with a GM dealer so see if dye is available which can be added to the trans fluid and then later checked with a black light.
I don't understand your comment about suspected slippage of the flywheel due to oil leakage. The flywheel (actually a flexplate on an auto trans) is bolted to the rear of the crankshaft and the torque converter is bolted to the flexplate. No way to slip unless bolts are sheared and then you wouldn't be able to drive the car at all.

 

[drags1998]

This may take a COUPLE OF TRYS, when you leave the car overnite,the torque converter may be draining back into trans. pan.If this is the case,& the seal around the dipstick tube is bad it may leak a little. The correct way to find it would be to take a piece of cardboard at least 4ft.square,slide it under the car and up tight against the front tires. Then after the car is driven,& it leaks onto the cardboard,Measure side to side and front to rear. Then you will know just where to look when you get it back up on the lift!!!!!!GOOD LUCK!!!!

 

[SPANISHVETTS]

When we returned from Poland I discovered a transmission leak under the Vette. (It had been parked for 3 weeks.) When I checked the level it was ½ Pt. low.

I have driven her 500 miles since and she has not leaked even a drop. I say it is mysterious:confused …my wife says the car missed me.

 

[RedRagTop]

In my case it turned out to be the dipstick grommet located at the front left side of the pan and just slightly above. Easy, cheap fix. Hope it solves your problem...
RJS

 

[shribe]

Gromet replacement????

In my case it turned out to be the dipstick grommet located at the front left side of the pan and just slightly above. Easy, cheap fix. Hope it solves your problem...
RJS

Hey RJS,
You said that replacing the dipstick boot/seal was easy. Just wondering what the best way is to this. I had my tranny rebuilt, and installed it myself. Things were going so well and so fast putting it in, I thought maybe I should replace the seal for the dipstick, and throttle valve cable. I decided not to because I got in a hurry. Big mistake, found one (or Both) of the seals were now leaking. I haven't got to it yet, but I was hoping it was the TV cable because it seemed much easier. That bolt that holds the dipstick and the tranny to the block took me longer to get in than the rest of it all combined. I figured I would have to remove exhaust, c beam and drive shaft, and tilt tranny back to get that bolt out again. Is there an easier way? I was dreading the thought.

Thanks!

 

[Moonunit 451]

I don't think so.

 

[jedi]

Update

Yet another leak has cost 3 times what it should have! ad

1st my oil pan goes, and the 4 tries it took to fix (after my buddy tightened the bolts too tight)ad and cost over $500 in repairs, and now it took 4 tries to fix my transmission gasket leak.

1. $93 at Jiffy lube
2. $127 at Amoco to tell me Jiffy screwed up.
3. An hour of work lost to have Jiffy check their work and denig anythig is wrong
4. $99 at Sterling Chevrolet to diagnose Jiffy Lube screwed up and over torqued the bolts.
5. Chance to finally drive my vette once the weather warms up.......Priceless

So for a normal everyday replacement of my transmission gasket and filter it cost me $319 :cry

I have to find a worth while mech in the area, or I won't be able to afford to keep my vette. Oh and Sterling found another screwup by Phohanka , seems my intake valve failed again. That is the 4th time that it would have to be replaced. Pohanka had to do it 3 times before they fixed it 6 months ago, and it failed again , but there is no way in h#ll I will go back to them.
Jedi