I ran 180 miles to day all interstate ran at 72 mph there and back light reset
overhead started at 13.8 went up to 19.3 then must have went in to regen droped down to 16.1 then went back up to 18.2 on the way home same thing droped to about 17.1 then back up to 18.4. I went back to the same pump and filled up hand calc. showed 18.67. this is the best I've gotten usaly 15.5 to 16.0 mpg so far love the truck no problems truck was flashed the day I bought it 6-30-07. It was in Iowa flat. Making same run in the morn. will post how it did.

 

Glad to hear it.

 

Congrats on the mileage. Im seeing about 16+ mpg probably 70% hwy 30% city, mileage wise. But time wise i spend about 50/50.

so you are saying that your overhead is pretty accurate? there are very few who claim this. mine is pretty accurate. within a few tenths.

 

Mine appears to be cosistently 1 mpg off. It reads 15, I hand calc. 14. That's what I'm hearing around here, also. I have a friend w/ an '06 2500 that claims 25 mpg. I think he's relying on the computer, and resetting on a downhill w/ a tailwind. :-)

 

My overhead is pretty acurate especially over a LONG distance. Right after filling up, I carry approx. 140 gals with the aux. tank, the overhead will read about 1 m.p.g. higher than actual, but then will settle back down. I have a TRAX II digital fuel monitor guage that came with the aux. tank which I depend on to track my actual fuel mileage.

 

My overhead is consistantly off 1 mpg. I have almost 13000 miles and over the life of the truck I'm averaging just over 14 mpg, thats towing, town, highway, hotrodding. Got the truck May 22, with 32 miles.

 

Rowdy,
You may want to check on flash/upgrades. My 2007.5 is doing exactly what the first post showed, but I have never seen the 1mpg to start with. Mine is consistant at better than 18 unloaded hiway. My computer is .1 to .2 higher than hand calculation on a full tank. 7K miles

 

So Nacho, your tag line doesn't tell us much about your rig. Is it a stick or auto? What gear ratio? 2 wheel drive or 4x4? SRW or DRW? Anything else about the truck that could have a positive or negative impact on fuel mileage?

 

286 miles today hand calc.17.4 . Got my oil changed today and had them flash comp. and turn on idle up. never had cel light come on but told them it was on so they would hook up scaner foung code p1451 dont know what that is but still runs the same. overhead showed 18.4 when i filled up

 

17.5 is the best I could do so far, that is with no load, all stock, coasting down hills, 90% highway, keeping rpms under 2000/65mph.

 

I made a trip yesterday, over 400 miles. I averaged right at 17mpg Hand calc'd. that was averaging over 75mph. I dont like to travel that fast and would normally do about 65-70mph at most, but had to keep pace b/c i had no idea where i was going so i was following some one.

I feel that if i had stuck to 65-70mph i could have easily got 17.6-18mpg. Also that mpg figure includes 20-30 minutes of in town stop and go driving and quite a few WOT's during the 400 mile trip.

On a side note, the last couple tanks, my overhead seems to be right at 10% more than hand calc'd figures. I wonder if there is a way to get that fixed since it always seems to be 10%, it seems like some formula or constant somewhere in the programming could be changed.

I feel this fuel mileage is really good considering I only have right over 1400miles on the truck now!!!

The truck has the newest AU software version.

 

In the city, my overhead usually reads around 13-14. On highway toting 20k, I see 8.7-9.5. But i usually do 70-75 mph since I only have 3.73's. I would do 65-70 if i had 4.10s. im impressed i guess. since truck still has paperplates. I can get 285-300 miles before fill up, and thats before gas light comes on!!!!! If I were unloaded all highway, i can get almost 600 before fill up crusing at 65-70 mph.

P.S. I do luv this truck though, U cant even feel anything behind u if your toting 7k. That includes braking!!!!