TH350 module adjustment
Thread Starter
Drifting
Joined: Nov 2004
Posts: 1,971
Likes: 7
From: Longwood Florida
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 !!!!
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.
Burning Brakes
Joined: Apr 2004
Posts: 847
Likes: 0
From: Des Allemands LA
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
ltlevil
Thread Starter
Drifting
Joined: Nov 2004
Posts: 1,971
Likes: 7
From: Longwood Florida
Originally Posted by fl_rider
the screw is down inside the tube.
IF it is an adjustable modulator.
You will need a skinny screwdriver.
IF it is an adjustable modulator.
You will need a skinny screwdriver.
Yes it is gold!!
Melting Slicks
Joined: Feb 2003
Posts: 2,529
Likes: 27
From: Auburndale Florida
2025 C2 of the Year ('64-'66) Finalist - Unmodified
St. Jude Donor '03-'05-'06-'07-'09
Just got an adjustible modulator for my TH400......what direction do I turn to RAISE the shift points.....In or Out?
thanks
Mark
thanks
Mark
Le Mans Master
Joined: May 2002
Posts: 5,086
Likes: 786
From: Lebanon Township New Jersey
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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