So, My wife and daughter and I took a vacation at the beginning of July. We drove from outside of Toledo, Ohio to Olive Hill Ky. On the way down I got 20.1 MPG's. Round trip I averaged 19.5 MPG's. I have a 2010 RAM 1500 SLT/Big Horn edition. 4x4 Quad cab. I have a Bull bar, step tubes (Raptors) bed cover. I am pretty happy with the MPG's I have gotten. After all it is a 5200# plus TRUCK
I just finished travelling Winnipeg Manitoba to Vancouver British Columbia and back (about 5000 Km or 3000 miles) pulling a 16' car hauler and 3000 lb vehicle. I got from 15 mpg in mountains to 24 mpg on flat land. I'm very happy with this and had power to spare at all times. My truck turns 1500 RPM at 100 Kph (60 mph) with loaded trailer or without.
Just returned from a 2,200 mile roundtrip to Packers training camp in Green Bay. Got about 23 mpg when strictly on highways with less in city traffic. Overall for the 2,200 miles averaged 19.8. Made nearly the same trip a few years ago in a V6 Ford Explorer and got 17 highway and 14.5 in the city. I'll take the 390 HP Hemi's 19.8 any day!