I have a 2014 Ram 3500 with the 6.7L Cummins which I bought new and it now has 75K miles on it. Modern Diesels are pretty easy to live with and get better fuel milage than their gas counterparts. If you are OK with keeping the DEF tank full (not a big deal at all) and changing 100.00 Fuel filter/water separator every 15K miles, to me it's a no brainer..... I guess the oil changes are also 12 quarts.... The upside is I can pull my 27' travel trailer or big boat over any hill about as fast as I want and the motor doesn't struggle or hardly down shift. I personally like the factory exhaust brake for coming down long grades when towing and the interior on the trucks is roomy and well done.
I run 35" tires and still get an average of city and highway driving of 17 mpg. When I pull the travel trailer I'm at about 13 mpg. No complaints from me.
