2014 Silverado 2500HD MPG

I do believe you will get between 8 and 10 mpg. We tow a Jayco HT 26.5 RLS and a 19 Crestliner with our 2012 D/A crew cab GMC 2500HD and get, generally close to 12 on the highway. We took the FW only on a 3,500 mile trip last spring to Idaho, Nevada, Yosemite and Sequoia National Parks, Palm Desert, Zion and Salt Lake City and then home and got 12 mpg over the whole trip. But diesels will get better mileage pulling the same loads and that's why I say between 8 and 10. Our old 454 Vortec would get 8 mpg and our old diesel pulling the same loads would get around 12, approximately 50% greater mpg.