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SCOTI · 10-25-2003, 11:26 AM

http://67-72chevytrucks.com/vboard/s...threadid=74290

BLACK AND BLUE 67-72 · 10-25-2003, 03:38 PM

UUMMM? What kind of help are you needing? It looks like on the last posts your questions were answered. They only make two types of vacuum modulators: Adjustable and the stock Non-Adjustable. Most every aftermarket modulator is adjustable, it has a small screw inside where the line hooks up (It should come with instructions on which way to turn it) And yes you can adjust it for quicker firmer shifts or later softer shifts. You are actually supposed to replace them every 10,000 miles, but no one ever does. The instructions are as follows:

1. Carefully break seal at adjusting screw by applying torque to screw.

2. To eliminate soft shifts or slippage, turn modulator adjusting screw in a clockwise direction two (2) full turns. Reconnect vacuum tube to modulator and road test. If soft shifts or slippage still exist, turn modulator adjusting screw clockwise an additional two (2) full turns. Reconnect vacuum tube to modulator and road test. If soft shifts still exist, consult a transmission specilist.

3. To eliminate harsh shifts, turn modulator adjusting screw in a counterclockwise direction two (2) full turns. Reconnect vacuum tube to modulator and road test. If harsh shifts still exist, turn modulator adjusting screw counterclockwise an additional two (2) full turns. Reconnect vacuum tube to modulator and road test. If harsh shifts still exist, consult a transmission specialist.

CAUTION: DO NOT adjust clockwise (in) more than four (4) turns as further adjustment can cause damage to engine and transmission.
I hope this helps you.

10-25-2003, 11:26 AM	#1
SCOTI Registered User Join Date: Apr 2001 Location: DALLAS,TX Posts: 21,940	Tranny Help Needed http://67-72chevytrucks.com/vboard/s...threadid=74290 __________________ 67SWB-B.B.RetroRod 64SWB-Recycle 89CCDually-Driver/Tow Truck 99CCSWB Driver All Fleetsides @rattlecankustoms in IG Building a small, high rpm engine with the perfect bore, stroke and rod ratio is very impressive. It's like a highly skilled Morrocan sword fighter with a Damascus Steel Scimitar..... *Cubic inches is like Indiana Jones with a cheap pistol.*

10-25-2003, 03:38 PM	#2
BLACK AND BLUE 67-72 Firefighter Join Date: Feb 2001 Location: Yellville, Ar, USA Posts: 1,943	UUMMM? What kind of help are you needing? It looks like on the last posts your questions were answered. They only make two types of vacuum modulators: Adjustable and the stock Non-Adjustable. Most every aftermarket modulator is adjustable, it has a small screw inside where the line hooks up (It should come with instructions on which way to turn it) And yes you can adjust it for quicker firmer shifts or later softer shifts. You are actually supposed to replace them every 10,000 miles, but no one ever does. The instructions are as follows: 1. Carefully break seal at adjusting screw by applying torque to screw. 2. To eliminate soft shifts or slippage, turn modulator adjusting screw in a clockwise direction two (2) full turns. Reconnect vacuum tube to modulator and road test. If soft shifts or slippage still exist, turn modulator adjusting screw clockwise an additional two (2) full turns. Reconnect vacuum tube to modulator and road test. If soft shifts still exist, consult a transmission specilist. 3. To eliminate harsh shifts, turn modulator adjusting screw in a counterclockwise direction two (2) full turns. Reconnect vacuum tube to modulator and road test. If harsh shifts still exist, turn modulator adjusting screw counterclockwise an additional two (2) full turns. Reconnect vacuum tube to modulator and road test. If harsh shifts still exist, consult a transmission specialist. CAUTION: DO NOT adjust clockwise (in) more than four (4) turns as further adjustment can cause damage to engine and transmission. I hope this helps you. __________________ '72 Chevy SWB 350 Auto '67 GMC LWB 350 4 speed '70 Chevy 4x4 Stepside 350 Auto Yellville, Ar. USA



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