Want a wild guess? I used to own a RAM 1500 Bighorn with a V-8 about 8 years ago. That was a great truck but only a 2WD so I eventually had to sell it when I bought a boat. On boat ramps, it is best to have a 4WD. So I replaced the RAM with a 4WD Grand Cherokee. I would guess around 16 MPG city/highway for the RAM. That depends on if you are a lead foot and how fast over the speed limit you typically drive. Their mileage drops dramatically the faster you drive over the speed limit.

I would pick a RAM over a GM or a Ford any day.