master tech
is the man when it comes to transmissions!

 

This sounds exactly like my problem. I have a 2002 Dakota QuadCab 4x4 with 62K miles and had a shifting problem going up a hill. I have since replaced the Accumulator plate, screws and three accumulator piston rings. I found the broken accumulator bolt heads and two destroyed accumulator teflon rings in the pan when I dropped it to inspect valve body but I had to replace three of the rings in the third and fourth pistons (only one good ring out of the four).

I could not find the missing third ring and put everything back on, replaced fluid and thought I was done. The truck ran fine for about 200-300 miles and then one day the Check Engine light came back on and the transmission felt like it slipped a bit shifting from 2nd to third. Engine code was p0733 (3rd gear shift ratio) and it only happens when the truck warms up. Replaced output speed sensor on tranny with one from Autozone but the Mopar original appeared functional on a meter.

Could anyone suggest other things to check. I'm about to drive it to a transmission shop but I feel like I would get ripped off.