my SC 5.5 bed, max tow on 20x10 weld wheels and 295/55/20 ridge grapplers with 2" level gets 19.5 mpg 50/50 highway. i only run top tier gas, mainly sunoco 87 octane. i would run 93 and get around 21 mpg but @ $4 a gallon thats alot money w a 36 gallon tank lol i figured over 700 miles a tank is...