Author Topic: Automatic Trans Problem  (Read 2834 times)

Offline johnnymk

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Automatic Trans Problem
« on: July 06, 2007, 05:24:57 PM »
My '83 Chevy C10 pickup has a TH 350 from an '85 Chevy. The truck sat for over a year up until 2 months ago.

I had replaced the lower transmission pan gasket last year because it was leakng. I drove it and there was a delay in upshifts. I found out the vacuum line to the trans was split. It was great after that.

Well, a lot of transmission fluid was leaking onto the driveway recently. I couldn't tell, but it appears it is leaking again from the lower pan gasket. I had to add nearly two quarts of fluid. I drove it a few miles and it was slipping really bad. After another mile, it wouldn't go forward anymore. I coasted to the side of the road. I had it towed home.

It goes in reverse.

Could the slipping of the trans ruined something internally? 

What should I look for when I take the pan off? Metal shavings?

Offline VileZambonie

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Re: Automatic Trans Problem
« Reply #1 on: July 06, 2007, 10:30:16 PM »
First check the fluid level again. Check that the detent cable is adjusted properly and that your vacuum hose is good still.

If it's still slipping in all forward ranges then it's time to rebuild it.
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Offline Lt.Del

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Re: Automatic Trans Problem
« Reply #2 on: July 07, 2007, 01:05:10 AM »
Make sure your trans fluid is checked when the engine is hot.   If it then shows you have good fluid level and it still slips, rebuild is in order.

Offline johnnymk

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Re: Automatic Trans Problem
« Reply #3 on: July 07, 2007, 11:17:17 AM »
Dropped the pan...gasket is rubber, no cracks. Filter has a lot of particles. Pan has some floaters. I tried to scoop one up, but I ended up mashing it. It's definitely brass or copper colored.
I think I destroyed the clutches.

The leak is coming from the front of the trans cover. And it appears that the little O=ring in the yoke is leaking.

I have never rebuilt an automatic, just a few manual transmissions. I looked at one of the links you have from Car Craft magazine, but it says the trans rebuild instructions is for up to 1981. Same directions?

How long would it take to rebuild this, assuming everything goes smoothly? Does it ever? ;D

Offline johnnymk

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Re: Automatic Trans Problem
« Reply #4 on: July 09, 2007, 03:04:40 PM »
Here are my options: Rebuild the current tranny. $100 for a rebuild kit, $130 for a torque converter. I have never done this before, so I am reluctant to do it.

A friend of mine has a late seventies 350 trans from a Z28, no lockup torque converter, just a stock one, correct length tailshaft. He thinks it's in good condition. Cost-free.

Take it to a local transmission place. $700 includes torque converter, free towing and 12 month warranty.

Hopefully, the rear main seal is one piece. Then he could replace it at the same time.

Offline Lt.Del

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Re: Automatic Trans Problem
« Reply #5 on: July 09, 2007, 10:33:09 PM »
Quote
Hopefully, the rear main seal is one piece. Then he could replace it at the same time.

I'd prefer a two piece.  It doesn't take long to replace a two-piece and don't have to drop tranny.