Used diesel buying question

I sold my 08 Titan and bought the pre-emission Ram in my signature. At the time I towed a 6,000# travel trailer. I know it isn't fair to compare a half ton short bed to a long bed dually but towing was night and day. Towing mileage went from 9 mpg in the Titan to 13.6 mpg. I have towed a 4,000# boat with the Ram and returned better mileage than with the Titan empty. Drivability with the diesel is fine, in my mind enjoyable. Noise is an issue. Granted it doesn't get really cold where I live but the seat heaters and exhaust brake make the weather a non issue. Maybe it is due to my year of truck but maintenance is easy as everything is very accessible plus not expensive. In four years reliability has been good, just filters and fluids. The depreciation down slope on the Titan was starting to get steep, the Ram is currently on a flat spot. I've been so pleased with the diesel that it was my single requirement when shopping for an SUV. Good luck with your search. Finding a clean pre-emission diesel that hasn't been rode hard, lifted or modified isn't easy to do.