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TH350 module adjustment

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Old Jul 12, 2006 | 08:25 PM
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Default TH350 module adjustment

I was told by the gentleman that built my tranny that the vacuum module on the end of the vacuum hose a tiny little screw in it...

I should back that screw out about 2 turns to lower my shift points. Well...I think I found the module... passenger side of tranny with a vacuum hose on it... mine is a gold color. (guessing it is the module)

I need to lower my shift point while the car is in drive... it tends to shift at about 3500 or more...

He told me he guessed on the settling not know what kind of vacuum my C5 LS1 motor would make.

anyway... when I looked at what I thought was the module... no way I could see a screw in it... laying on my car with a car about 3 inches on the ground...

is there truth to this...


RANT
Why is it what happens when I pay somebody to work on my car... I always need to work on it when i get it HOME !!!!

Last edited by holley505; Jul 12, 2006 at 09:48 PM.
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Old Jul 12, 2006 | 08:28 PM
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Default

They do make adjustable modulator valves (the gold thing). Usually they're adjustable for a few miles an hour at most. I'd also look at the passing gear cable, sounds more like what's causing the long shift times.

ltlevil
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Old Jul 12, 2006 | 08:54 PM
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Default Take the vacuum line off...

the screw is down inside the tube.

IF it is an adjustable modulator.

You will need a skinny screwdriver.
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Old Jul 12, 2006 | 09:47 PM
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Originally Posted by fl_rider
the screw is down inside the tube.

IF it is an adjustable modulator.

You will need a skinny screwdriver.
it is in the tube not the module?

Yes it is gold!!
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Old Jul 12, 2006 | 10:36 PM
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Just got an adjustible modulator for my TH400......what direction do I turn to RAISE the shift points.....In or Out?
thanks
Mark
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Old Jul 13, 2006 | 07:46 AM
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On my TH350 trans, the guy who built it said to lower shift points turn the tiny screw inside the gold modulater clockwise. I turned it 1/4 turn and lowered full throttle shift about 400 rpm.
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Old Jul 13, 2006 | 08:47 AM
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will he told me to back the screw out to lower it... so that would be counter clockwise to lower it??
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Old Jul 13, 2006 | 09:53 AM
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I would think backing the screw out would be counter clockwise.
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