between the front suspension not supporting the weight of the cummins, the added size and depth of the cummins made making the PW suspension a nightmare, and the intercooler and larger radiator that is needed if you tow with a cummins stops the winch from being hidden. At least thats what a Factory Sales Rep that was at a local dealer told me. He did say they prototyped one, (not sure how true it is because I have searched for it and not found it)