Transmission leak
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Joined: Jan 2010
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From: Columbia PA
Transmission leak
I was driving my 1992 corvette coupe 6 speed the other day and I noticed a good amount of smoke in the car and trailing the car. So I jacked it up a week later and the right exhaust pipe (where the exhaust pipes comes together to run parallel together to run under the drive shaft) was wet looking. And right above that the two bolt to that brace from the trans to the rear end, those two bolts look like where fluid was dripping from. Now I'm thinking It may be the trans rear seal. But I'm not sure. And I'm wonder if draining the trans and refilling it and adding stop leak would help. I don't want to take the trans out unless I have too. I would like to drive the car with out looking like it's about to catch fire. Any advice would be great.
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From: Charlotte NC
I...personally would NOT add anything to the fluid to stop a leak that a seal can repair.
Not looking at what the cause of the problem is...you might have a bushing in the tailshaft that is also needing to be replacing with a yoke due to wear.
Just make sure that if you do any repairs and the 2 bolts that hold the support beam to your tailshaft housing are removed. These 2 bolts have a SPECIFIC torque value. SO do not just use an air impact....or you may be SORRY.
DUB
Not looking at what the cause of the problem is...you might have a bushing in the tailshaft that is also needing to be replacing with a yoke due to wear.
Just make sure that if you do any repairs and the 2 bolts that hold the support beam to your tailshaft housing are removed. These 2 bolts have a SPECIFIC torque value. SO do not just use an air impact....or you may be SORRY.
DUB
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From: Columbia PA
I checked the oil level. I jacked up the driver side of the car so the fluid level was off but the fluid that did come out of the check plug (I couldn't take the plug out because of the side I jacked up on, all the fluid was against the plug) the fluid looked really good. It surprised me. So it doesn't look that old
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From: moraga ca
If the leak is not coming from the pan, there is a good chance it's coming from the rear tailshaft housing seal or the 0 ring between the tailshaft housing and the transmission. Replacement of both of these don't require dropping the tranny. With the C-beam removed, the rear of the trans can be tilted down and the 4 bolts accessed. The speedo sensor needs to be removed in order to get one of the driver's side bolts off. I would replace the tailshaft bushing along with the seal and the 0 ring. The yoke might have a slight groove from the rear seal. That can usually be emery clothed and polished out.
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Joined: Apr 2009
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From: Charlotte NC
I checked the oil level. I jacked up the driver side of the car so the fluid level was off but the fluid that did come out of the check plug (I couldn't take the plug out because of the side I jacked up on, all the fluid was against the plug) the fluid looked really good. It surprised me. So it doesn't look that old
OOOPS...this is a 6-speed which does not have a pan.
DUB
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From: Charlotte NC
NO problem...if that is you in the car in your avatar...LAUNCHING...You have a prefect explanation on missing a word or two when you are reading things....it is because your mind is trying to catch up to where your body is currently. 
DUB
DUB
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Joined: Jan 2010
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From: Columbia PA
Ok I finally had time to look at the car better. I bought home so wax and grease remover from work and I cleaned the area really good and check the trans oil level with the car sitting level and it was just a touch below the fill plug hole. Then I took it for a drive to get the temps to normal ranges and to get it to start smoking again and I bought it back home and jacked it up to see where it was leaking but I didn't see anything obviously leaking but the exhaust was still smoking good. I was thinking a rear trans seal but now I'm not sure. I'm wondering if a intake manifold leak could be my problem. I do know I have a small oil leak and I know the intake gaskets are known for leaking. The oil I see leaking is at the back of the oil pan, the shield of the trans, starter and filter. There just minor but I can see fresh oil at those spots after I drove the car. Basically could oil from the intake run to the back of the trans? I just figure I ask.
Last edited by ccorvetteracing; Aug 1, 2014 at 05:45 PM.
Instructor
Joined: Jun 2011
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From: Brunswick Georgia
Ok I finally had time to look at the car better. I bought home so wax and grease remover from work and I cleaned the area really good and check the trans oil level with the car sitting level and it was just a touch below the fill plug hole. Then I took it for a drive to get the temps to normal ranges and to get it to start smoking again and I bought it back home and jacked it up to see where it was leaking but I didn't see anything obviously leaking but the exhaust was still smoking good. Is smoking coming from exhaust or from under the car?
I was thinking a rear trans seal but now I'm not sure. I'm wondering if a intake manifold leak could be my problem. I do know I have a small oil leak and I know the intake gaskets are known for leaking. The oil I see leaking is at the back of the oil pan, the shield of the trans, starter and filter. There just minor but I can see fresh oil at those spots after I drove the car. Basically could oil from the intake run to the back of the trans? Not if it is just minor.
I just figure I ask.
I was thinking a rear trans seal but now I'm not sure. I'm wondering if a intake manifold leak could be my problem. I do know I have a small oil leak and I know the intake gaskets are known for leaking. The oil I see leaking is at the back of the oil pan, the shield of the trans, starter and filter. There just minor but I can see fresh oil at those spots after I drove the car. Basically could oil from the intake run to the back of the trans? Not if it is just minor.
I just figure I ask.
Clean ALL oily areas, then see if it smokes.
.
.
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Joined: Jan 2010
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From: Columbia PA
I cleaned the bottom of the engine and trans yesterday and after I drove it, it still was smoking and there was oil drops at the back of the oil pan, front shield if the trans, and the bottom of the starter, but the rest of the trans was still clean. It looks like the smoke is coming from the exhaust. I checked all fluids this morning and everything was full but the engine oil was about an 1/8 of a quart low or less. It always had a minor oil leak, about a nickel to quarter size puddle on the floor but this morning it was 2" long x 1" wide under the back of the oil pan and the front if the trans. My dad thinks oil is leaking from the engine and blowing back on to the exhaust. By the way I have the 3" cat back exhaust from corvette central.
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From: Milwaukee Wisconsin
Trans leak
I have a 86 and the trans pan gasket leaks. I have tried cork rubber sealer and I get it to slow down but it still drips. I even bought a new pan. Any tricks that some one might have to help?
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Joined: Jun 2011
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From: Brunswick Georgia
I never use gasket sealer, just a lil grease on pan to hold gasket in place while tightening.
Number one cause for leak is over-tightening the bolts, very lil torque is required, especially with cork.
Be sure leak is not coming from somewhere else and showing up at the pan area...
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Joined: Apr 2002
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From: Anaheim CA
I have seen (on my car) the front seal leak and the ATF runs down the front of the pump and out through the gap at the bottom of the torque converter cover. From there it goes to the front of the pan and appears to be a leak in that area.
Farpak gaskets were recommended to me by Dana Wilkes at ProBuilt Automatics. I have never had a leak after switching to the Farpak gaskets.
Farpak gaskets were recommended to me by Dana Wilkes at ProBuilt Automatics. I have never had a leak after switching to the Farpak gaskets.
Last edited by Cliff Harris; Aug 20, 2014 at 03:00 AM.