mike2wheels wrote:
On a recent trip to Mississippi from Arizona I averaged about 12, with most miles towing a 12000 5er, but with a couple of days empty. Most tanks avg about 10.x while running 60-65 mph. If I tried to maintain 65 the mileage dropped to 9.x. The truck has 4.10 gears and the automatic. When running empty at 70 mph I get about 17 mpg.
That's pretty good mpg, I had a 2010 Ram 3500 Crew cab, dually/longbed/4X4 with 4:10 in Laramie trim, and running empty, if at 70 mph, never saw 17, think I may have gotten a little over 15, but that's in the mountains....Towing my 5er at 16,050#, depending on direction I towed in the mountains. mileage sounds about the same, except I normally ran 55-62mph, on occasion might hit 65....again, all driving I did was in the mountains.
I do get better mpg with the 13', but it's with the addition of DEF
Having re-read post, I would say almost all of your driving was in "flatland", though not that familiar with terrain from Arizona until you hit TX border, (if that's the way you went).