Ok I did a search on How to adjust a C6 Tranny Modulator, and found some info after some work, but it is sparse at best.
So I will try to discribe the best I can. I titled it so maybe it will be easier to find in a search.
I jacked the car up and supported it. According to all the instructions I could find, you pull the vacuum line off the modulator and put a small screw driver in and turning clockwise raises the shift point counter clockwise lowers.
Sounds easy enough.
Well, hummmmmm, ok I am under the car. I see the modulator. Hummmmmmmm, Sure looks like that tranny support bracket is in the way. Ahhhhhhhh yup Ain't no way to get the vacuum line off, and even if I did, Ain't no way to get a screw driver in to adjust it. The tranny support completely covers the end of the Modulator. Ok Get the small jack out and a piece of wood. put it under the tranny to support the tranny so I can take the Support off.
once you have the 2 bolts off lift the tranny just a touch with the jack then take the bolt out off the wide end of the support. This should be on the passenger side. It is a 9/16th Socket on one side wrench on the other.
once the bolt is out you should be able to swing the support down. If it is to hard to swing down Loosen up the other bolt on the drivers side. then it will swing right down. Ok now you can see the whole modulator. Pull the Vacuum hose off. Used a fine very small straight slot screw driver and turn it clock wise. You usually don't want to start with more than a 1/2 turn but I went 3/4.
Then you have to put it all back together again to try it. If not enough you have to go through the whole proccess again.
So there you go. Not so bad, But not as easy as I have found directions for.
Remember! this is for a C6 in a 71-73 Mustang.
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