Unless you're pulling a heavy load--such as the aforementioned fifth-wheel--Harper guessed this Ram would get 15 to 20 mpg. With the new 60-gallon tank, that can mean a range of 900-1200 miles.

Transfer Flow sent us one of its 30-gallon toolbox and refueling pump systems (PN 080-01-12975), which would not only give us the option to shop around for the best diesel price, but at 17 1/2 ...