usually I get like 17-20 on my overhead.

I got diesel earlier and drove 50 miles about 65-70 mph and when i got home it says 28.5mpg on the overhead.... is that even possible???

 

Need you ask??????????

 

i dunno was no head wind and its not real hilly or anything.

i've just never seen it off by that far before so why would it start lieing hard core now???

 

I do not think so. Must be bad readout on overhead...maybe if you were going downhill all the way with a tailwind.

 

wierd i just drove around oklahoma city for the past hour and now its down to 23... thats so wierd i even reset it once... my truck is smokin crack

 

Got 31 one way then 15 the other way, yepper it was windy...

 

You sure your console wasn't reading in metric?

28.5L/100Km is something like 11MPG...

 

If I reset my overhead while coasting it will display ridiculously high numbers. Normal driving will eventually bring it back down to Earth.

 

the fueling boxes always confuse the overhead. the overhead calculates mileage based on a few sensor inputs like throttle position sensor and boost.

with these fueling boxes throwing more fuel for the same throttle position and for example stock it takes 40% throttle to maintain 65mph, it now may take 30% throttle to do the same. the same amount of fuel is being used, just more power is being produced with less throttle input. confuses the overhead a bunch.

 

i think its possible because i left charlotte nc one morning going to work at 6am no traffic and set my cruise on 60 mph

i drove about 30 miles and just before i go off the interstate i was at 25 mpg

now i have seen as much as 26.5 on level ground at 55 mph

this is with a 2wd, quad cab, with no mods,17k miles, auto,2003 model

if i had a single cab, 80lbs in tires, and a fresh air system,with a box, and more miles on the truck, with a 6 speed, i feel sure i could get a least 28 mpg

 

I don't know boys, I get 23 real regular with my 2wd dually; but the only way to know for sure is to fill'er up and divide it out the old fashioned way!
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03 2WD Dually, QC Auto

 

I would not believe the overhead ever. Mine says it is -40f when it is 65* outside. It does it all the time. There should be some room for air, but not 105*.

 

There's a TSB for that you know. Happened to mine and they fixed it.