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Old 01-30-2014, 09:45 PM   #1
ZMAR
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TH350 won't upshift

I've checked the fluid while everything was hot. Good there. Pulled the governor out and shook it, plunger is working freely. Vacuum is ran and hooked to manifold not carb and free of any cracks or kinks. When you take off in drive it revs way up there and won't shift. It's like you push the clutch in and it idles back down while you are still rolling. Any ideas here fellas?
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Old 01-30-2014, 09:55 PM   #2
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Re: TH350 won't upshift

How is the gear on the governor?
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Old 01-30-2014, 10:04 PM   #3
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Re: TH350 won't upshift

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How is the gear on the governor?
Looked brand new
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Old 01-30-2014, 10:09 PM   #4
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Re: TH350 won't upshift

And you checked the drive gear as well on the output shaft? Did you verify there is vacuum with the engine running at the vacuum modulator? Is the detent cable hooked up and properly adjusted?
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Old 01-30-2014, 10:12 PM   #5
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Re: TH350 won't upshift

Is it slipping or just revving high? Check the downshift cable for proper adjustment. If its too tight it will try to stay in passing gear.
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Old 01-30-2014, 10:23 PM   #6
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Re: TH350 won't upshift

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Originally Posted by Sabaka454 View Post
And you checked the drive gear as well on the output shaft? Did you verify there is vacuum with the engine running at the vacuum modulator? Is the detent cable hooked up and properly adjusted?
I didn't look inside the hole where the governor slides in. It did rotate when I pulled it out and it came out very smooth. So I unhook the vacuum line at the modulator w/ motor running and see if there is vacuum? I did not look at the cable but will check that right now
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Old 01-30-2014, 10:28 PM   #7
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Re: TH350 won't upshift

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Is it slipping or just revving high? Check the downshift cable for proper adjustment. If its too tight it will try to stay in passing gear.
Revving high. It has a stall in it but I doubt it's 5k! I'm going to check the cable
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Old 01-30-2014, 10:29 PM   #8
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Re: TH350 won't upshift

What about completely unhooking the cable? What would that do? It's got 38s and super low gears
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Old 01-30-2014, 10:47 PM   #9
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Re: TH350 won't upshift

The cable is not too tight.
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Old 01-30-2014, 10:51 PM   #10
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Re: TH350 won't upshift

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How is the gear on the governor?
That was my thought. Had one get so hot on one side it melted it down to a smooth indentation. The rest of the gear was find except that one spot.
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Old 01-31-2014, 06:00 PM   #11
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Re: TH350 won't upshift

Check for vacuum... keep the kick-down cable on there you'll want it with the 38s, regardless of your steep gears.
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