Which one of these vehicles gets the best fuel efficiency? The Dodge Ram weighs 7,800 pounds empty, and these Wranglers weigh 3,400 pounds trail ready. A turbo-diesel powered truck, this unloaded Ram averages 24.3 or more mpg highway. A turbo-diesel engine is much more fuel-efficient than a gasoline engine. The Ram gets better off-pavement fuel efficiency, too. Consider a modern, "clean tailpipe" turbo-diesel for your next rig. The turbo compensates for altitude, too!