I wouldn't have any issues over choosing between a Hemi truck and any diesel truck, but then, I'm not driving 25,000 mile a year either. In addition to the better fuel mileage, you need to add the higher upkeep costs, the higher up front cost, and the higher price of fuel for that diesel truck. I'm betting the cost breakdown over a 5 year run given the same mileage will probably be pretty close to each other, or lean towards the gas powered truck.

Then, you really need to determine how often you really will be towing with that truck, or how often you really needed a truck at all, out of the 25K miles a year your driving. How does the cost of either truck compare to what a car would cost over the same time/miles?

I suspect you would be ahead of the game if you updated your D100 for the towing purposes, and maintain your current car for daily transportation, until it needs to be replaced because it died. Having been around car dealerships for many years, I don't buy into the "value of a trade in", its a big lie. But then you don't get something shinny and new. Gene