marrs1721

jcb206

NC2TX

X2 for true MPG calculate it yourself. miles driven/gallons used (keep in mind it may still be inaccurate if tires are not stock)

bassJAM

Your "average" will be immediate and greatly depend on your driving conditions. I'll have days were I'll reset and there will be no traffic on my commute and my average for that day will show 20-21 mpg, but by the end of the week and I get into the normal stop and go it'll drop into the 18's, which is what my true average is.

Also, do a hand calculation. It seems most of the computer averages are 2 or more mpg optimistic. I'm one of the lucky one's, mine is only 0.5mpg high.

I feel like in the dash settings you can also make sure that towing doesn't affect your average mpg calculation.

Eduskator

How did you get those numbers? If you did not hand calculate them (or use a phone app.), it's not even worth debating! I'm pretty sure your 26MPG shown is more a 20MPG.

If you did reset it and drove 100% highway, it's normal for it to be high. I reset my trip 1 every time I fuel up and it's a lot more accurate than the ''average mpg'' shown on the fuel consumption screen.

FYI, the ''break-in'' period is 1000miles.

bisjoe

Yes, it depends a lot on the conditions. I can fill up at the gas station at the top of the hill, reset and drive to the freeway, and when I hit the on-ramp it shows 50 mpg. By the time I get off at work it's back to the more normal 19-20. If I fill up on the way home in the flats, reset and then go up the hills to the house, it can read as low as 12. Last weekend I used about half a tank returning from a weekend camping trip towing our trailer (5,000+ lbs.) and it showed 10.8, and now after two trips to work it's still only at 12.8, because I didn't reset.

redrock

Pitiful that truck owners now obsess over fuel economy numbers. You can thank automakers for featuring gadgets that make drivers ****-retentive.

All that's important to me is miles-until-empty. I sleep better at night.

bassJAM

It has nothing to do with "gadgets", and everything to do with gas prices and money. I've cared about fuel economy since I started driving 20 years ago.

The only thing the gadgets have done is fool a handful of owners into believing their truck is more fuel efficient than it really is. Seems to be a Big 3 problem too, for some reason my wife's Honda and my old Nissan managed to accurately calculate the mpg average.

Gene K

So calibrate the LOM! It's not like it takes over a couple of minutes. My 2.7 was off 5-10% Depending on time of year and number of cold starts before I calibrated it.

Gene K

Calibrate none pushbutton start (They are slightly different: play with it or search).

1. Press and Hold OK
2. Turn Switch to On (Without Starting) and after about 5 seconds "Engineering Test Mode" Message will appear.
3. Release OK and message will change to "Gauge Test"
4. Press OK approximately 32 times to get to "AFE Bias".
5. Press OK to enter into adjustment and use arrows to adjust.

It will be set on 1000. Divide calculated mpg by display mpg to get new Bias.
IE 18.00/20.00=900.
Most of the 3.5EB need around 934 but go by your own measurements as number of cold starts, time of year, specific gravity of fuel batch and truck to truck variations will all effect it.