hii i have a 91 dakota 3.9 4x4 4 spd auto, its just had alot of work done to it. i recently pulled out the tranny and replaced the front seal because it was pouring fluid. it did fine for about 3 months and here we are. it will shift through 1-3 just fine, no complaints, but it will only shift into fourth when i let off the gas almost comletely. ill get up to about 40 or so and it is ready to shift into fourth, but it wont untill i basically let off of the gas and let it roll then it will shift fine and i can continue. any sugesstions will be appreciated...thanks!

 

That is typical of lots of older style systems. But the 4th geat/Over Drive (OD) is electronic activated. The speed sensor and throttle position sensor tells the PCM when shift into OD. So one of those may be bad, not all bad sensors/electronics need to set off a code or be completely dead to be bad.

 

ok, so the tps is on the throttle body right?, and the speed sensor is on the transfer case??

 

yeah the tps is right there on the throttle body. very easy to do. If your broke you may try cleaning it. The speed sensor is either on the transfercase or trans. Not hard either.

 

i pulled out the speed sensor and cleaned it and it works fine now