New to the forum. I now have a 2002Ford F350 with the 7.3 powerstroke. I use it for interstate use pulling stacked boat trailers with my own authority. I pull 6 trailers on a tri axle hauler and 2 trailers overhead on a rack that goes from front to back. I weigh 11,400 empty (with the empty haul trailer) and usually around 22,000 loaded. My Ford gets 8mpg avg loaded and 12 empty for an average of 10. I am looking at a 2006 Dodge dually (5.9 with 3.73 gears) and 26k miles as a replacement for the Ford, only for increased fuel milage. I average 8000 miles per month at 10mpg is $3200 in fuel for the month @ 4.00 gal. My Dodge dealer says he thinks I can avg 14 with the Dodge and if that were the case my fuel cost for the same 8000 miles would be $2284, a savings of $900.00+ per month. My question is simply this, will this truck get 14mpg avg, half the miles loaded and half empty (keep in mind empty is still with the tri axle haul trailer and the rack on the truck). The 22,000 lbs loaded is not the only issue when I am loaded, it is wind resistance. When I am loaded with 8 trailers it is like pulling a parachute down the highway so the motor is always in a strain. I am in business for myself and VERY fuel conscience usually travelling loaded at 55mph and empty at 60-62 mph. It is imparitive that this truck can get 3-4 mpg better than the Ford or it would not be worth the extra $$$ spent in truck payment. So please, your thoughts. I never mod my trucks (other than open exhaust and air intake) as I am pulling so hard all the time that I would worry about EGT with mods. Thank you for your time!