Just put chr146 in my ram 6.4 at 86k miles. I always had a hard shift 1-2 since it was new. Also, the occasional slippage going up steep incline in like 2nd. I need the truck to last me another 3-5 years so went ahead and did this upgrade as more of a preventative measure. Followed the instructions closely and added the proper springs, ended up having no issues doing this in the driveway at my house. I’ve only put a few hundred miles on it since but so far, every shift is smooth as can be. Might update this after a few hundred more and getting some towing in but I am pleased with results. Not sure i would trust this as fix if I had major issues already though. Also, this is my 3rd trans fluid/filter change and hardly anything on the magnet in the pan.
Just an fyi, I ran the relearn twice after bringing up to operating temperature and switching back and forth drive/neutral reverse. I didn’t trust calibration on first go around because I assume it would be bad data if all the orifaces/accumulators weren’t completely purged of air.
Hopefully this info helps someone