Thread: need help !! I need to raise the shift points on my th 400 trans

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I just had my th 400 rebuilt, but I don't like where it shifts. it shifts out of first at 20 mph, then out of second at 36 mph, how can i raise the mph where it shifts, I would like it to shift out of first around 30mph and second at 45 mph. also if I am driving faster than 36mph and floor it, it won;t kick down into pass gear, if I am driving less than 36 and floor it, it will shift down. is that normal?? what needs adjusted?

Shift points are determined by the vac modulator on a Turbo 400. It does not have a cable like the Turbo 350. You also need to check the downshift points. That is actuated by an electrical signal or switch hooked to the throttle some how in most cases. Aftermarket Vac modulators will respond to lower amounts or signal if you have a wilder cam.
Remove the hose from the unit and turning screw inside the tube that the hose pushes on is how to adjust. IN is a higher RPM..... give her 2 full turns as a start point.

yes it has a pretty radical cam, and it has a adjustable mod., I will give it a coupe of turn in, thanks. will let you know how it works.

i have a manual valve body in my th400 make my own shift points. didnt think that i would like but its fun.

yes line pressure make it shift this work off the govner and the modulator i have had all my 400 trans with reversed manual valve body this way have the same one from 1981 but there is no gearbraking .so if you want it to shift it self than a govner kit and a bit of valve body work you may want to do

Try a shift kit, it comes with different tension springs and shims, just pull the pan (drain oil first) pull out valve body and install shift kit. ! thing you really want to make sure of is thAT YOU HAVE THE STEEL DAMPENER BALLS and not the rubber ones they wear and make all sorts of weird shifteing patterns.