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Old 10-11-2007, 05:11 PM   #1
JHART
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Tranny leaking - Cant find from where - HELP!

Ok .... i have BRAND NEW TH350 with a shift kit installed in my truck and the thing is pissing me off.

Anytime i let the truck sit for a lengthy period like a week or more it leaks tranny fluid ... and allot of it. Cant figure out where its coming from but i cant keep letting this happen.

Any ideas? I really dont want to but if i have to i will rip the thing back out of the truck and take it back to the shop. But i dont have time for that right now i am in the military getting ready to deploy.

Any advice is greatly appreciated.

-Hart
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Old 10-11-2007, 05:23 PM   #2
Luvlegs
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Re: Tranny leaking - Cant find from where - HELP!

I'd start with some cardboard underneath to help spot where the leak is dropping from then follow back to where it's leaking - try to toss a little sand on the cardboard (thin layer) - that way, if it puddles and runs off, you can get a better idea of where it's actually hitting.... I say all this assuming you just cant find any fluid on the truck... One other thought, check your coolant - could it possibly be leaking through in the radiator (if your's is run through the bottom part of it)... good luck.
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Old 10-11-2007, 05:25 PM   #3
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Re: Tranny leaking - Cant find from where - HELP!

My 400 turbo does that after I let it sit for more than a week. Did that since it was freshly rebuilt.
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Old 10-11-2007, 05:28 PM   #4
JHART
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Re: Tranny leaking - Cant find from where - HELP!

Thats what i am saying is this normal?
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Old 10-11-2007, 05:37 PM   #5
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Re: Tranny leaking - Cant find from where - HELP!

Shouldn't be "normal" I have my engine and tranny mocked up and my 400 is leaking from the dipstick tube. I've had this tranny in two different vehicles and after the first rebuild it didn't do it. after the second it has, I think the o ring is too small.

Might want to check the pan gasket aswell those things are easy to squash, which causes them to leak.

Frank
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Old 10-11-2007, 05:40 PM   #6
JHART
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Re: Tranny leaking - Cant find from where - HELP!

I checked the pan ... gasket still looks brand new and no residual fluid anywhere.
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Old 10-11-2007, 05:53 PM   #7
brianthelion02
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Re: Tranny leaking - Cant find from where - HELP!

As youre tranny sits idle,the torque converter will slowly drain back into the transmission and fill it up beyond where the fluid while the motor is running,soo you need to check the oring seal at the detent cable and also the selector lever shaft seal may be bad,either one doesnt require removal of the tranny!!When the trannyn is in use everyday it usually wont leak at these points cause the fluid stays in the torque converter,this is a very common problem and easily fixed!!!!!!!Good luck!!!!!!
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Old 10-11-2007, 06:26 PM   #8
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Re: Tranny leaking - Cant find from where - HELP!

Look at the dipstick, vacuum modulator, kickdown cable, and possible the input shaft seal in the front of the pump. Remove the dust cover under the flywheel/flexplate and see if it is oily below where the converter slides into the trans. Front pump seal means removing the trans to fix it...

Brian
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Old 10-11-2007, 09:44 PM   #9
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Re: Tranny leaking - Cant find from where - HELP!

Mine did the exact same thing. It drove me nuts, but turned out to be very simple. The dipstick tube was re-installed into my brand new tranny with the original old o-ring. Then when the fluid in the torque converter would drain out after a couple of days it would leak all around the edge of the pan and drip from about 15 different places.

All I did was pull the dipstick tube, put on two (it may only have needed one, but I figured two would be better) new o-rings, put it back together, and it hasn't leaked a drop since.
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Old 10-11-2007, 10:39 PM   #10
longhorn70gmc
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Re: Tranny leaking - Cant find from where - HELP!

http://67-72chevytrucks.com/vboard/s...d.php?t=257913

Hello,
No that is not normal and the thread above talks about this same problem and what we did to fix it. The issue is quit common amonst our trucks. I stopped the big leak, so now it wants to come out the o-ring seal in the tail of the transmission. Good luck on your fix. Look forwards to hearing how you fixed it with out removing the tranny.
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Old 10-11-2007, 10:42 PM   #11
crzngmychvy
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Re: Tranny leaking - Cant find from where - HELP!

Same problem, and I've tried a few times to find the problem, but haven't yet.
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