I've got a stock 08 Mega with the 6-speed auto, 3.73 gears, 4x4, and srw. Unloaded I get 14 around the city and 17 on the highway (hand calculated, meter reads a little higher) . I have yet to get numbers loaded.
Empty on the last time I hand calculated was just over 19 but I keep it around 70mph, mostly Interstate, 590 miles on just over 30gal. Never hand calculated loaded but last time had a over load of about 2000lb of sod and the over head said 16 on a 120miles hwy. We do about half hwy half town empty most tanks and usually right around 16, around 490 miles give or take. my over head has been pretty acurate on the hwy. seems to be all over the place in town reading 11-19 with no ryme or reason and will stick on 67 deg.
A forum community dedicated to Dodge Cummins Diesel truck owners and enthusiasts. Come join the discussion about reviews, drivetrain swaps, turbos, modifications, classifieds, builds, troubleshooting, maintenance, and more!