Quote Originally Posted by MetalheadLLC View Post
First time Cummins owner here, so that definitely qualifies me as a noob in this realm. However, I am no noob to vehicles in general. Just trying to sort out something out here without knowing the idiosyncrasies of these trucks.

What I have:

2012 3500 ST DRW
150K miles
WELLLLLL maintained
Previous owner took it in to the Dodge dealer EVERY service interval.
He did not have any of the modifications, he had it bone stock, I just put these on yesterday after I had a Edge Juice w/ attitude on it for maybe 2000 miles:
RaceME Ultra
5" Flo-Pro Turbo Back

What's going on?

I have the truck on "Default" 120HP tune, and I am gentle as I am well aware of the 68RFE shortcomings and also the lack of overboost protection on the box tunes. The issue I am having is between 3rd and 4th gears, and somewhat between 4th and 5th. When it gets ready to shift to the next gear it's as if it hesitates, like it can't decide whether or not it wants to shift or not. From what I've researched, it shouldn't be the transmission itself slipping as I am not getting any CELs. However, I know that there are issues with valve bodies and torque converters so that is where I am currently leaning. I'd rather not take it to a shop as I am capable of making repairs on my own (short of a full transmission rebuild, voodoo and sorcery in there to me at my current skill level). But if I don't know the exact issues, then obviously I cannot know what exactly to do. I'd greatly appreciate any insight, or correction to my current ignorance on these trucks. Thank you all in advance!
You must be old like me

I'll bet it doesn't do it during a heavier pedal. It's a typical electronic trans control. The trans is on a threshold to shift, and the sensor can't make a definite decision for the controller. It's hunting. The all do it. Even our Hyundai dos it