I just bought a 2006 dodge ram 2500 cummins diesel the other day and i love it. I havent let it go through the whole tank of fuel yet but when i fill it up from 3/4 of a tank it shows i'm only averaging 14.5 mpg hand calculated and that with driving pretty easily, that is mixed driving town and highway. my truck already has a bully dog air intake and a edge mileage max chip. i dont know why its getting that low any thought of what it could be or what i could do to make it better thanks!!!

 

You're barely getting better MPG than my 6.4 DPF truck & I drive it like I stole it.

 

i know i havent changed the fuel filter since i bought a couple of days ago so i might try that. i dont know how long ago its been changed since i bought it from a guy i hope that it it

 

If you've only used a partial tank of fuel, you haven't used enough to get an average yet. Even hand calculating that small of an amount isn't relevent. Drive it and go through some full tanks and then figure it by hand.
Stay safe out there.
Ken

 

My '07 5.9 exhibits a wide range of unloaded MPG behaviors. It goes from a high of 21 on long highway trips to a low of 13 if I'm mostly shuttling around town and getting into it alot. Normal average is 18 in mixed driving if I take it easy. You will probably see that over the long term as well like blacktruck says, if you are a conservative driver. Heavy on the throttle and it drops quick.

 

okay thanks guys i appreciate the help and advice!