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Potentiometer for auto trans shift adjustment problems

3K views 12 replies 4 participants last post by  country_hick 
#1 ·
I wired in a potentiometer like in the wiring diagram splicing into the black and light blue ground and it does not change anything. I could only find a 5K ohm pot at Radio Shack, not the 500-1000 ohm in the wiring diagram. Any thoughts/suggestions? I travel like a grampa, so no lead foot. 0 to 60 in about 45 seconds....Thanks
 
#3 ·
On second read, I think I know the wiring diagram your taking about with the pot on the ground circuit. To me, that one makes no sense if your trying to address a bad TPS. What you want is to put the middle wire from the plug to the middle of the pot and the other two on the sides of the pot. Take the tps out of the equation completely and use the pot in leui of the tps.
 
#4 · (Edited)
What I am trying to do is lock the tc around 30-35 mph for best in town MPG, and then reset if towing anything. How would it work without tps input?
How would the transmission know when to shift? Electronics are alien to me....
thanks
 
#5 ·
Shift points are a combination of speed and rpms and throttle position, etc. The potentiometer tricks the throttle part so the shift into 4th happen when you decide.

For tc lockup around town, do a tc lockup switch. To delay shifts to 4th or to deal with a bad tps, do the potentiometer mod.
 
#6 ·
Boy, I must have been really tired last night.....Trying to get to 5th as low as possible getting through the gears sooner and keeping rps low in town for better fuel economy. Basically giving me choices on shift points.

By the way, how do I do a tc lock up switch too?
Thanks
 
#9 ·
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#10 ·
OK added the potentiometer and now it shifts into OD around 30. Excellent!
Wired the TC switch, but no lock up...will see if I did it right or if it is the computer....Wired the orange and black to the power side of the switch and the ground to the ground side.
Should I wire any to the accessory port instead?
Thanks
 
#12 ·
I think there is more to it for 47re. If you have a 96, I don't think you can just ground out the pin 54 like you can on a 94-95 which has the 47rh.

Read the first page of that instruction sheet from tst that country hick posted.
 
#13 ·
It is possible your PCM needs to be reflashed. Some trucks made between 2 dates shown in the tst link above do not lock up without a reflash from the dealer.
 
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