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Transmission Leak

J

jmbour66

Member
I took the 73 vert out for a nice long drive today and she ran great! She was responsive and would go from 60 to 90 in no-time, I was happy as all get out until I got back to my house and an hour later noticed she was dripping transmission fluid.....I recently changed the tranny fluid (during an engine transplant) and put in a new pan gasket........

HELP! :wtf
 
Re: Tranny Leak

What part of the tranny was the leak from? Did you over torque the pan on the reinstall? Is you dip stick in all the way? Just thinking out loud.
 
Re: Tranny Leak

What tranny are we talking about? Stock oil pan? If that's the only thing you touched then yes you might have warped the flange around the bolts. But also if it's an automatic, what about the lines going from the tranny to the oil cooler if you have one?
 
Re: Tranny Leak

It's a C4 Automatic, it appears to be leaking from the front of the bell housing, but this could be the lowest point and the fluid is just ending up there. I don't have a separate cooler.

thanks.
 
Re: Tranny Leak

Sounds like possibly a front seal.....look for oil inside the bell housing.

Most of the time, the leaking oil will blow to the back of the tranny.

Check the dipstick tube where it mates to the tranny body. Also, are there any splices in the lines running to the radiator?
 
Re: Tranny Leak

"tarafied1" said:
He means the lines that go to the radiator
Click to expand...

Yup. Since they had to be disconnected and reconnected for the removal/install, just thought that this needs to be quickly looked at. It would be sweet this this was the culprit and not the front seal or oil pan.
 
Re: Tranny Leak

It appears that the leak is actually manifesting itself behind the front lip of the bell housing on the drivers side.... :confu

On further inspection: It appears that the leak begins 3/4 of the way up where the bell housing meets the block (drivers side). When the engine is running hot the fluid comes out very thin (so thin that when it drips on the header it acts more like steam then smoke) and then thickens as the engine cools, it eventually stops dripping all together........

am I correct in my thinking that the bell-housing itself should be free of Transmission Fluid? And if so, then this would lead me to believe that either I have a bad seal or a bad pump......
 
Re: Tranny Leak

That sounds high for a seal leak. They normally splatter around inside the bell housing and then drain to the bottom and drip....

Any possibility that the vacuum modulator is bad and fluid is being sucked towards the intake with some leaking from the hard line to the rubber line?
 
Re: Tranny Leak

"AzPete" said:
That sounds high for a seal leak. They normally splatter around inside the bell housing and then drain to the bottom and drip....

Any possibility that the vacuum modulator is bad and fluid is being sucked towards the intake with some leaking from the hard line to the rubber line?
Click to expand...


:shrug Where would I begin to look?

Would there be any other symptoms? When I first put the car into gear, the transmission probably takes 3 to 5 seconds to engage. The car has done this for so long that I stopped paying attention.......
 
Re: Tranny Leak

If the vacuum modulator is bad, you might also see some smoke from the engine burning the tranny fluid.

There is a line, normally metal, coming into the engine bay in the back passenger side on the tranny. It connects to a rubber line that attaches to the intake manifold in the rear of the engine. The vacuum modulator is on the passenger side of the trann, near the back....at the other end of this line.

There is not supposed to be tranny fluid in this line...if there is the modulator is bad. The hard line to rubber line near the intake is what I was referring to.
 
Sounds like its coming out of the dipstick tube, possibly over filled and when its getting hot its coming out the filler tube. 3/4 of the way up the block on the drivers side.
 
"Fast68back" said:
Sounds like its coming out of the dipstick tube, possibly over filled and when its getting hot its coming out the filler tube. 3/4 of the way up the block on the drivers side.
Click to expand...

My Transmission Dipstick is on the passenger side.....
 
"jmbour66" said:
My Transmission Dipstick is on the passenger side.....
Click to expand...

There's the whole problem....lol....not really....the C-4 dipstick tube should be on the passengers side.
 
"AzPete" said:
There's the whole problem....lol....not really....the C-4 dipstick tube should be on the passengers side.
Click to expand...

Now you tell me, I spent the better part of the last day relocating it! Just kidding.

but seriously, would a bad modulator effect shifting? because other then being slow to engage (when the car is first put into gear), the transmission seems to shift great.
 
Depending on if it is real bad or just getting weak, it could feel good....main tell tale is fluid in the vac. line from it to the intake.
 
Well, I finally got around to checking the vacuum modulator and there was no fluid in the line, however the leak still persists.

At this point I 'm thinking of having the transmission rebuilt and I'm wondering how much I should expect to pay. Any ideas?
 
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