My F250 diesel (2006 6.0) is decent on fuel 18mpg empty highway, 11mpg towing a fifth wheel trailer. But maintenance is expensive, and counterbalances any savings on fuel. Oil changes are 15 quarts plus a $24 filter. Fuel filters need changed every other oil change and cost $50-60 a set (there are two),and a new turbo cost $700 + $1100 in labor. Plus diesel fuel has been consistently about $.90/gal more than gasoline. If you need to tow over 8000-9000 pounds, the diesel is warranted. If not, the gasoline engine is likely a better choice.