Duramax 3.0 using too much def?

[Dersch]

I have 12k miles on mine. I have added 10 gallons total to mine maybe 12.5 can't remember.. i do 90% highway.

 

1500 miles ago i filled it up pretty much full and its saying i only have 150 miles left... this seems like way too much?? 

 

I filled it up day one full that lasted me close to 5k-6k miles. Ever since then i feel every 2000-2500 miles it needs filled up. 

 

Im about to fill up the tank full at 12k miles and will monitor how many miles it lasts. 

 

[rbdjr]

I have approx 10,500 miles on mine but I dont tow much, I bought it new in July, 3.0L, 4x4,crew , so far I have gone  through 6 gals total maybe not using enough? Maybe im not pushing it enough? Mileage in August down to virgina and back was just over 34mpg diesel,  around town now Im getting between 24/27 mpg diesel.  

[Dersch]

4 minutes ago, rbdjr said:

I have approx 10,500 miles on mine but I dont tow much, I bought it new in July, 3.0L, 4x4,crew , so far I have gone  through 6 gals total maybe not using enough? Maybe im not pushing it enough? Mileage in August down to virgina and back was just over 34mpg diesel,  around town now Im getting between 24/27 mpg diesel.  

I bought mine new in june.... crew elevation 4x4. 

 

I have never towed with it. I don't hot rod it and i rarely leave it idle too. 

 

I do however have 6" lift and 35s... but i can't inagine thatd cause me to use almost double of you...