I have a 2002 Durango and it doesn't want to shift. You have to completely let off the throttle and wait. The problem carries through the gears but more pronounced in the 1-2 shift. I unplugged the TPS and nothing changed. No codes until I unplugged the TPS. I'm not too familiar with this rig. Maybe a cracked vacuum line or a bad TPS? I tested the TPS and got 1.4-5v with one combination and .45-4.4v in another. Without a diagram I can't be sure which combo was correct but 1.4-5 sounds really high. Any educated input is greatly appreciated.

 

I'm not sure why your not getting a code but you might have a problem with your input&output speed sensors there is two on the transmission just a thought. Mine has similar issues and will find out tonight if it is one of those sensors

 

I replaced the TPS and tranny output speed sensor with no luck. The more I drive it it seems like the problem is mainly the 1-2 shift. Everybody's telling me to flush the tranny but that has never solved any of my problems personally.

 

any luck yet sounds like the same problem my boss is having his truck holds first until 5000rpm he did a flush on the tranny and a filter with no luck.