Im having trouble with my truck,taken to long to shift, and then it shifts up an down some times. The bands are fine the valve boby is new, it dose this when I give it full throttle, when taking off. Dose it with the lock up swicth in or out. Some times while in overdrive it shifts in outof OD, but with the lock up swicth on it will stay in od. My ? is could it be the TPS ? I have worked on many nv45oo s and 56oos, its the first auto I have ever had. Truck is a 94

 

you have a govenor / throttle valve issue. Try adjusting the TV cable first, if that does not work you will have to dig deeper to the govenor.