no that is checking at the pump

yeah just keep in mind u cant trust the overhead or dic because your computer still think it had factory tires and wheels and like the dmax is 245 and my dic says on adverage 15 and i can easily get 17 in town AND 20 highway on adverge and like one time my mom:w2: was with me on a roadtrip and i got 24 thats with everything listed below 285 ect :rocking:

best i have seen my DIC read was 25 on the way to dallas with listed mods.....but that was cruising at 72

My box stock LLY 5-Speed was getting 18 MPG (calculated) at best……until it hit 20K. Then it was like there was a switch in the odometer. The power seemed to increase as did the fuel mileage. On a trip to Reno traveling 60-80 MPH with the cruise on I averaged 24.7 MPG (calculated).

My 07 Classis LBZ 6-Speed will turn 20K this week and I have done the air box mod and have a CTS on “1”. The dash is reading 22.5 MPG for a freeway average which I do not pay much attention to as the LLY was off 0.3 MPG. I will be traveling to Reno at the end of the month and will calculate my MPG but I expect it to be in the 22-23 range. The 2007 is heavier by 250 + pounds because of some factory options………We shall see.

my 07 classic is stock on the hwy i get 17-21 mpg depends on conditions @ 65 to 75 mph and in town is 13-15 mpg.

Mine is bone stock with the stock tires and gets 19-21mpg @ 55mph. 13-14 mog in town if I baby it. If you want to break a Dmax in and get good mileage, hook 10000-12000lbs up to it and take it on a 5000 mile ride. They are pretty consistent after that. Don't trust the DIC as it is usually off a couple MPG and is resettable.

i have a o7 lbz, edge with attitude, k&n intake, 5 inch strait pipe and on level three with a clean filter get about 24 empty and 18 dragging my 38 foot fithwheel

my friend has i think a 06 duramax 4x4, 4 door and he gets 15 mpg no matter what and his truck is really clean

I have an '07 classic with an LBZ, and I've tried stock and with a Superchips on economy mode trying to get better fuel mileage, but the best I can do is average around 14.5-15 mpg, that's hand calculated. I run 265/75-16 tires and I drive it like I'm trying to conserve fuel. The worst day of my life is when I sold my '02 Dodge with 24v cummins, 5 sp which averaged 18.5 mpg and was getting better when I sold it. Shame on me.

try a better tuner than superchips...... I now run an EFI tune of 365rwhp and can 18-19mpg mixed town and highway:jump: