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Old 09-06-2010, 09:31 PM   #1
hdandd
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Question Not 2 happy

My tranny wont shift into 3rd gear anymore... last time it did that it was just out of time but i re timed it and it still wont shift, any ideas?
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Old 09-06-2010, 09:43 PM   #2
Indyuke
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Re: Not 2 happy

What type of transmission?
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Old 09-06-2010, 09:57 PM   #3
Bad70sbchevy
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Re: Not 2 happy

Did you check the transmission fluid level?
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Old 09-09-2010, 04:21 PM   #4
hdandd
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Re: Not 2 happy

Turbo hydro matic
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Old 09-13-2010, 12:08 PM   #5
hdandd
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Unhappy Re: Not 2 happy

Its not the tanny fluid... it sat for about 18 hours, when i drove it it shifted into 3rd the first time a accelarated but not anyother times..
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Old 09-13-2010, 12:16 PM   #6
mr48chev
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Re: Not 2 happy

Did you knock the vacuum line off that goes to the trans? That happens a lot when a guy is working in that area setting the timing or tightening the distributor down.

Also make sure that the hoses on both ends of the steel line to the modulator are in good shape an not split or swollen and soft.
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Old 10-29-2010, 03:43 PM   #7
hdandd
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Re: Not 2 happy

The tranny line is good
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Old 10-29-2010, 04:55 PM   #8
planewhisperer
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Re: Not 2 happy

Your vacum line may be cracked or have a hole in it. Do you have vacum advance?
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Old 10-29-2010, 05:18 PM   #9
JCD
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Re: Not 2 happy

Quote:
Originally Posted by hdandd View Post
Its not the tanny fluid... it sat for about 18 hours, when i drove it it shifted into 3rd the first time a accelarated but not anyother times..
This has happened to me twice.. with a Firebird, and a Corvair..

Someone else will chime in with the correct part name.
It's a sealed plunger that shifts the Trans into high gear..

What happens is, when the fluid is cold, it's thicker, and the plunger works..
But as the fluid heats up it becomes more watery and can no longer actuate the plunger into high gear..
If you're in high gear on the highway or on a road.. the moment the trans kicks down into 2nd, it won't go back up into high gear..

If you let it sit for a few hours, it'll work fine until it heats up again..

J.
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Last edited by JCD; 10-29-2010 at 05:19 PM.
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