Tires and MPG

[Johnasara]

The best I can get is 20-22 on the road with the tuner on 120 its the same in the road as on 85. But in town it went up now its fun to drive

[daddysLBZ]

Originally Posted by subparwelder

Mine sucks as well. Only have about 9k on it and praying that it gets better with time. Getting 14-15

Give it some time and keep your filters clean,etc.Use some cetane boosttoo,it can't hurt in moderation..I know it should get better as time goes by,mine did..It got a straight 16-17 at best stock....But after the tuner and exhaust were added,it got better as time went by..Keep in mind a lot of stuff affects mpg..Different Duramaxes have different comp ratios,different turbos,5 versus 6 speed transmissions,winter blended fuels,and really on and on....Tires also add to the equation,every movement the truck makes is through the tires too....Hope it picks up fer ya though!!

[DenverK16]

I am getting almost 19 MPG and i have 35's with 22's and thats not being easy on it all the time i keep my tuner on the 120 hp and it gets really good mileage on that setting