I have a 2012 3500 Ram with a 2014 6.7L diesel and tranny installed in my 2012 3500. After the install of the engine and tranny the tranny had problems. I have installed a new shifting module. the tranny is an a default mode. I was told I have to have the module flashed by a Dodge service center to get it to shift correctly. Currently it has only the fourth gear and reverse. It slams into gear when shifted to drive. It is an automatic.