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Old 06-28-2005, 03:40 PM   #1
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Default Adjusting an Adjustable Modulator

My priorities may not be straight, but I picked up a new [adjustable] modulator, for my '89 [this is what they gave me, you cannot buy a fixed one anymore]. It is much smaller, but it'* the same, in that it is totally compatable and whatnot. It is what came stock on the 4T60-E. Anyways, I don't know how to adjust it, and I want to know how.

Also, I compared the top needle thing on it to mine, and this one doesn't push in and is very firm, yet mine goes in half way no problem, and is easily pushed in the other half with very little resistance. Not to mention it lets ATF through the vacuum line, so it'* shot.

I bet any money that this makes a HUGE difference in transmission performance, especially in the 440-t4. So I want everyone to go pull theirs, and make sure it is firm the whole way around, and doesn't just fall in half the way through. Also be sure to pull your vacuum line to make sure it doesn't have ATF on it.


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Old 06-28-2005, 04:16 PM   #2
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Ok...I'll jump right on that.

Can you give us a little more info as to where, why and what you are talking about. I know it'* tranny but many might not.
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Old 06-28-2005, 04:52 PM   #3
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The vaccuum modulator controls transmission fluid pressure, and adjusts it by the amount of vacuum. And the amount of vacuum varies with idle and high rpm. So, basically it tells the transmission how high the pressure should be. And it also controls it, itself.

It is located on the front of the transmission, and on the 440-t4 is right by a connector, the connector for the gear switch [tells the ECU what gear the tranny is in].

The modulator is adjustable, to control how firm or soft your shifts are. No clue how to adjust it, and doing what does what on the modulator itself. Although my car may not run, it'* good information.


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Old 06-28-2005, 04:53 PM   #4
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Have you tried Googling the brand and/or part name to see if you can download a manual for it???
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Old 06-29-2005, 09:50 AM   #5
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Nope. I'm more curious what it'* effects are. Since I really can't play with it. I talked to three guys at autozone [I had a gift card.. I SWEAR!], and none of them knew how to adjust it.


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Old 06-29-2005, 09:55 AM   #6
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Toys are great, having installation instructions and directions on how to use the new toy...........................................PRIC ELESS
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Old 06-29-2005, 10:07 AM   #7
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lol they are. Too bad mine doesn't have any :(. I went to go look at it, and it seems it has a screw below where the vacuum line plugs in [accessable]. Should I try turning it?


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Old 06-29-2005, 10:12 AM   #8
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Quote:
Originally Posted by MOS95B
Have you tried Googling the brand and/or part name to see if you can download a manual for it???
Right..yours didn't come w/them...but maybe with a little research time you can find yourself a set.

I work on pinball machines a lot and if I can find manuals from the mid 70'* you can probably find a new product. Give it a try...you'll never regret it.
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Old 06-29-2005, 10:42 AM   #9
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Jeez. I Google stuff I have the directions for, just to see if I can find any tips on how to use it.

That'* how I found this site, after all....
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Old 06-29-2005, 10:55 AM   #10
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Nothing specific to the 440 was found, but TCI had some info on their transmissions, and adjusting it that way with the screw in the vacuum line nipple [like mine]. So my guess, that is the method

Quote:
Stock factory modulators are pre-set and most are sealed. TCIŽ StreetFighterŽ modulator-type transmissions are all equipped with adjustable modulators. By turning the adjusting screw (found in the vacuum nipple) counterclockwise, you will lower the spring pre-load. This will cause earlier shifts. By turning the adjusting screw clockwise and raising the spring pre-load, the shift points will go up. The range of adjustability is only a few mph either way.
.

Don't pay attention to the increasing shift points. That doesn't apply to us. Which I found out here. It'* got some good info on TV-Cables and Modulated trannies. Along with the procedure to change out the 1-2 spring to remove the 2-1 downshift clunk.

Too bad I don't have a car to test it on :(. However, I do still want everyone to inspect their modulator, because I know exactly how dependant our transmissions are upon it. It could make that harsh shifting slipping tranny into a smooth shifting beauty in no time.


-justin
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