I agree, a small diesel in something like the Power Wagon makes sense, but not the Raptor. Too nose heavy. Ford had every intention of putting the 4.4 diesel in the F150's. I think it was about 08ish it was scheduled for the 12. When the economy sank, the diesel F150 project went with it. I'm sure there were too many uknowns at the time. At least the Raptor, 6.2, ecoboost all survived.