trans leak
Thread Starter
8th Gear
Joined: Apr 2010
Posts: 8
Likes: 0
trans leak
have a 86 corvette that likes to leak tranny fluid when it is parked in the garage. i have don all the fluid tricks i could. when it is warmed up it does not leak, well maybe less than a teaspoon. it is leaking somewhere from the front, hoping not front seal. major job for a 3.00 dollar item.can't understand how a front seal would leak so much when it is parked. does anyone have any other idea's on this problem.thanks
Drifting
Joined: Aug 2006
Posts: 1,624
Likes: 2
From: Canandaigua New York
Check your trans lines first.
They run along the right side and if one is bad it could be spraying fluid from a pin hole.
And yes, it is a pain pulling a tranny for a 3 dollar seal, but it's the only way to replace it.
The reason it leaks when it's cold is because the metal shaft 'contracts' and creates a bigger gap between the worn seal and shaft.
When it warms up, the metal shaft 'expands' and it seals tighter.
They run along the right side and if one is bad it could be spraying fluid from a pin hole.
And yes, it is a pain pulling a tranny for a 3 dollar seal, but it's the only way to replace it.
The reason it leaks when it's cold is because the metal shaft 'contracts' and creates a bigger gap between the worn seal and shaft.
When it warms up, the metal shaft 'expands' and it seals tighter.
Racer
Joined: Jul 2010
Posts: 308
Likes: 2
From: Kansas City MO
Have you pulled off the 'dust shield' to check the converter / pump seal? If you suspect it's leaking there then pulling off the dust shield should show that it's wet. Other places it leaks that might look like the front pump seal is the pan gasket or even the shift shaft seal - the oil can travel along the pan rail and drip off the front - especially if the trans is level or the car is pointing nose down...
If it's not easy to tell where it's leaking from I usually start by cleaning everything down and then either parking it over some cardboard or parking it up on blocks/ramps or jack-stands to where I can get under it and then see where the drips show up...
If it's not easy to tell where it's leaking from I usually start by cleaning everything down and then either parking it over some cardboard or parking it up on blocks/ramps or jack-stands to where I can get under it and then see where the drips show up...
Safety Car
Joined: Jun 2006
Posts: 3,629
Likes: 28
From: FL
Another seal not yet mentioned that can cause this is the one for the dipstick tube. When the engine is running the fluid level is below the seal so it may not leak a drop, after sitting the fluid level rises and can reach a point above the dipstick tube seal.
Racer
Joined: Jul 2010
Posts: 308
Likes: 2
From: Kansas City MO
If your pan is in bad shape I'd recommend a cast aluminum upgraded piece - it's got a lot thicker rail and stays flat even against a bit of over-torquing..
Race Director
Joined: Apr 2003
Posts: 17,698
Likes: 1,667
From: moraga ca
Good idea above about flattening the gasket contact areas of the pan. I would nix the idea about rtv though. I drop the pan and pull my tranny out many times a year and I have never had a pan leak. Rtv would make cleanup a bigger chore and unnecessary work.
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Racer
Joined: Jul 2010
Posts: 308
Likes: 2
From: Kansas City MO
It's such a little bit (hence the caps on light) that it's more to hold the gasket in place while it goes together than to seal it up... you shouldn't see any squeeze out when tightened - that's how little gets put on...
Instructor
Joined: Sep 2010
Posts: 240
Likes: 0
From: Port St Lucie FL
its probably the front seal.
i just had mine done as well, i had to change the rear main seal and the oil pan gasket, while they had the tranny out, i also had them do the front and rear tranny seals.
It didnt cost that much, i had a local transmission repair place (a local business for 25 years) do it, he only charged me labor ($250), and i purchased all the seals/gaskets.
took them about 4 hours to do it...
pick a tranny place, they have all the tools and lifts to do it quickly.
i just had mine done as well, i had to change the rear main seal and the oil pan gasket, while they had the tranny out, i also had them do the front and rear tranny seals.
It didnt cost that much, i had a local transmission repair place (a local business for 25 years) do it, he only charged me labor ($250), and i purchased all the seals/gaskets.
took them about 4 hours to do it...
pick a tranny place, they have all the tools and lifts to do it quickly.
Race Director
Joined: Apr 2003
Posts: 17,698
Likes: 1,667
From: moraga ca
Agreed. To some people however, a little is a half tube. The stuff can ooze out inside the pan and gunk up the works.
Advanced
Joined: Aug 2010
Posts: 53
Likes: 0
From: South End Of Northern VA
Few Drips myself
I find after driving I also have a few drips on the dust pan and around the part shown in these pics. What is this part? The amount is nothing major, annoying for now. I found all the bolts to be loose on my transmission pan and one even stripped. I do not have a lift making this kind of work difficult. I did snug them all with a 3/8 drive. Should not be over tightened. I used teflon tape on the stripped one just to hold it in. I did not strip it 
I was thinking of getting a slightly larger bolt for this hole??????
http://www.motoemporium.com/test/149-4969_img.jpg
http://www.motoemporium.com/test/149-4970_img.jpg
http://www.motoemporium.com/test/149-4972_img.jpg
To the right side of the cat.
Thanks
I was thinking of getting a slightly larger bolt for this hole??????http://www.motoemporium.com/test/149-4969_img.jpg
http://www.motoemporium.com/test/149-4970_img.jpg
http://www.motoemporium.com/test/149-4972_img.jpg
To the right side of the cat.
Thanks
Advanced
Joined: Aug 2010
Posts: 53
Likes: 0
From: South End Of Northern VA
- Any idea why oil may gather on this area? And what are the little hoses?
Race Director
Joined: Apr 2003
Posts: 17,698
Likes: 1,667
From: moraga ca
I find after driving I also have a few drips on the dust pan and around the part shown in these pics. What is this part? The amount is nothing major, annoying for now. I found all the bolts to be loose on my transmission pan and one even stripped. I do not have a lift making this kind of work difficult. I did snug them all with a 3/8 drive. Should not be over tightened. I used teflon tape on the stripped one just to hold it in. I did not strip it I was thinking of getting a slightly larger bolt for this hole??????
http://www.motoemporium.com/test/149-4969_img.jpg
http://www.motoemporium.com/test/149-4970_img.jpg
http://www.motoemporium.com/test/149-4972_img.jpg
To the right side of the cat.
Thanks
I was thinking of getting a slightly larger bolt for this hole??????http://www.motoemporium.com/test/149-4969_img.jpg
http://www.motoemporium.com/test/149-4970_img.jpg
http://www.motoemporium.com/test/149-4972_img.jpg
To the right side of the cat.
Thanks
Advanced
Joined: Aug 2010
Posts: 53
Likes: 0
From: South End Of Northern VA
Helicoil
-J