I've always felt that when running at WOT, my truck shifts into overdrive at too high a speed. It won't shift until I'm doing 67-68 mph. If I am accelerating up a slight grade, that means I can't get it to shift into OD (even though once in OD it accelerates pretty good), since I can't get to 67 mph in 3rd gear.

I read Bushy's instructions, and measured the voltage at the center tap of the TPS. I read 0.707V. I tried adjusting the voltage to various lower values without effect. I'm now down to 0.470V and haven't altered the change up point at all. Anyone have any idea how low I go without damaging or effecting something else?

John

 

It wouldn't hurt to also check your TV Cable that goes from your throttle down to your tranny. That can be checked with engine off and you open your throttle to W.O.T., then you should still have about 1/4" or less play (able to push further) at the tranny location of that cable. Adjustment is at the throttle location, a tab that you can unlock/lock to adjust. Be CAREFUL though as that does change the pressure for the tranny on when to shift. Hope that helps. I have seen procedures on Bill's website. www.dieseltrans.com I think.