Since dealer replaced fuel injectors and reprogrammed ECM on my 2005 CTD Auto4X4 Ram 2500 3000 miles ago, my transmission shifts different and is sluggish at slow speeds. No codes showing. Did reprogramming from Fuel Injector replacement change the shift points of my automatic transmission? If so, is there a fix to return it the previous shift points?

 

The reprogram of the ECM is what most likely cause this thus the trans will have to relearn and it will take a few weeks for it to relearn how you drive from what I have read about it.