6.7 Cummins and an Allison would be good combo. Too bad after 3 years the rest of the truck falls apart around it.
It
IS a good combo. Drove that for a couple years at work. That engine is quiet for a Cummins. Enough torque that Id grind the rubber off the rear tires every 20,000 miles or so. Allison shifted prefect when not in regen, too.
First thing I'd do is delete it, though. If I could've done that to mine, Id still be driving it.
DPF regen fumes started making me sick, not to mention during the almost-constant regens, the trans would go into this weird tow-haul mode that would downshift extremely aggressive to keep RPMs up...which is dangerous as hell on snowy or muddy roads.