My 1991 Dodge Ramcharger, 5.2L, (318) V8, auto trans,. I have had this truck since it was built. I special ordered it and picked it up with 7 miles on it. I have taken great care of it, getting it lubed and changing all the fluids on a regular basis. Granted, my truck has
126000 miles, but it has always been very reliable and dependable, but lately it has started to shift hard and at high speeds. When increasing speeds, it shifts out of first as late as 20mph on the speedometer (don't know specific RPM), and the same reading when decreasing. It shifts into second around 30mph, third at 40mph and then fourth at 43mph. I have not really felt it kick into 5th (overdrive) lately. In addition, when braking, it also tends to downshift hard and when coming to a stop, just as I am about to be completely stopped, the truck downshifts and LURCHES right at the end of my stopping period. The worst thing of all is how hard it is shifting. It bothers me that it may be seriously hurting my truck.I may have a bad TPS, not sure if that can affect it, but I am planning on changing it to see if that helps or hurts. Also, my cruise control is tango uniform (TU) these days. Been a while since I used it, so I don't really know how long it has been inoperable. My engine codes say I have a short in the speed control, and again, I am not sure if that can cause any or all.
Please advise.
Thanks