Ram's corporate parent, Fiat Chrysler Automobiles, lent ENR a truck to test for a week, and it delivered on its fuel-sipping promise. My basic test method started by simply topping off the fuel tank at the start of the week and then going about my normal business. Errands included trips to the home center to pick up painting supplies and hauling around landscaping materials, as well as a few leisurely cruises. Seven days later, I calculated total miles driven divided by total gallons pumped into the tank during the same period.
The result was a nice surprise, with 20.5 mpg in city driving beating Ram's estimated 19 mpg with four-wheel drive and a 3.55 rear-axle ratio. The truck's computer said I had driven 19.3 mpg at an average speed of 21 miles per hour. Next time, towing will be in order to see how the engine performs under stress.