So I just bought a 3rd gen. Truck is in my signature. It is an automatic. Drove like a dream when I test drove it.

However after driving it for about 150mi today, I'm getting quite the annoying issues. When coasting or braking to a stop, it like lags in 3rd gear and then suddenly downshifts to first almost a bit late. It ends up shifting hard and has a noticeable jerk. Sometimes it's worse than others. Apart from that the transmission runs and shifts flawlessly.

I checked the fluid level and it was fine and fluid was clean and smelled like good ATF.

Is this just normal? I plan on changing the trans filters and fluid regardless.

I've read about having a quick learn done, how there can be filter and TPS issues, reprogramming the TCM, and many other things but I'm just not sure on the best route to take. I don't have a CEL but I haven't tried pulling codes from the TCM either.

Thanks for any help!

Btw truck has 190k on it. You would never know as it's pretty clean and drives like new (and I can say that cause I've drive a brand new RAM)

 

I should add I got the following codes from the TCM:

P0935
P1684

After reading the service manual for the 545RFE, I'm going to replace the pressure sensor and repair the sensor harness. Any other suggestions are more than welcome.