I wanted the EcoD last year, couldn't wait so I got a LL CC with 3.92 gears. I pull a 18ft enclosed V-Nose that weighs 6,200lbs on the scales. The hemi has way more than enough power to handle the weight, I get 9-10 mpg running 60-65. I pulled the sane trailer empty from GA with a 2010 6.4 f250, I only averaged 9mpg running 75-80 mph. I pulled the trailer with 6200 lbs from VA to IA with a 2005 f350 DRW 6.0 and got 8 mpg running 70-80 mph. So there are some real world numbers to help you guys out.