Author Topic: TH-350 keep leaking oil  (Read 5676 times)

lemarin

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TH-350 keep leaking oil
« on: August 08, 2016, 12:48:03 PM »
My original TH-350 been rebuilt completely recently, they add a new torque as well. It cost me close to 2000$ to have it removed, rebuilt and reinstalled in place. It was badly leaking by the torque seal and the pump.

Few days later, it starts to leak again...this time by the pan's gasket. Went back to the garage, they have put another gasket on the pan. Few days later, it starts leaking again....less then before, but there's still oil on the floor.

Any idea what could be the problem ? Is it a common trouble on the TH-350 ?
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ko-lek-tor

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Re: TH-350 keep leaking oil
« Reply #1 on: August 08, 2016, 01:12:12 PM »
Shop did not take a ball pean hammer to the bolt holes in pan to restore any distorted holes caused by overtightening. Or, there is a hairline crack in the trans case or the leak is not from the pan and needs further diagnosis?
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cook_dw

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Re: TH-350 keep leaking oil
« Reply #2 on: August 08, 2016, 01:56:20 PM »
Find a new shop to work on your car..

Kelley W King

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Re: TH-350 keep leaking oil
« Reply #3 on: August 08, 2016, 07:35:26 PM »
I agree with Cook, but most all leaks appear to come from pan because most leaks head that way. when you drive it to tests for leaks the passing air will blow it sometimes away from the source.
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ss jim

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Re: TH-350 keep leaking oil
« Reply #4 on: August 17, 2016, 01:27:11 PM »
I had something similar happen on a Turbo 400 years ago. Changed gaskets and fluid 3 times then decided that wasn't the problem. The selector shaft seal was the problem. Might take a look.

Jim

KevinW

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Re: TH-350 keep leaking oil
« Reply #5 on: August 17, 2016, 01:44:10 PM »
Also look at the cooling line fittings and dipstick tube O-rings.  Either of those could have a slow leak that will travel around the pan gasket while driving.

Kelley W King

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Re: TH-350 keep leaking oil
« Reply #6 on: August 17, 2016, 07:27:31 PM »
Check the spedo cable also.
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firstgenaddict

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Re: TH-350 keep leaking oil
« Reply #7 on: September 03, 2016, 11:56:29 PM »
Shop did not take a ball pean hammer to the bolt holes in pan to restore any distorted holes caused by overtightening. Or, there is a hairline crack in the trans case or the leak is not from the pan and needs further diagnosis?

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TRLAND

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Re: TH-350 keep leaking oil
« Reply #8 on: September 04, 2016, 09:13:17 PM »
Also check the kick down cable fitting. It's right above the pan so it could look like it's coming from there.
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