2017 f-150
I know they are probably not THE most accurate thing but currently mine is giving me a reading that seems highly unlikely..
Up until now the "low gas" warning at 50mi left was working OK.

Today I have it saying 54mi to empty while the gas gauge is at 1/4 tank.
Seems ridiculous.
Now that reading was before the trip. I was sort of assuming the miles to empty calculation would sort of reset after that trip.

Now this truck gets very little use and at times only goes like 5-10mi city stop/go trips (yea I do battery top offs the correct way supposedly)

This last trip though was 80 miles and averaged 20.6mpg. Equiv to like a months worth of "normal" driving.



Suppose there is no reset or calibration thing..

 

You can reset right from the steering wheel buttons on the left. There is some adjustment that can be done with Forscan involving tire size and a few other inputs. If you search here using Google for [ recalibrate DTE F150forum.com ] you find plenty of threads covering your concern. 20.6 mpg isn't bad with what little info you give about your truck.

 

Yea the trip data can be reset..

Doesn't change the "miles to empty" data.

Anyways checked to see the size of the tank. Just never thought about it before . 23gal.. 1/4 tank approx 5.75 gal
I'll throw 1 gal out for reserve though ?
4.75
4.75 x 20 = 95 miles to empty.
Obviously it probably used some of the city driving for the estimate.

I "suppose" 50mi to empty with the gas gauge showing 1/4 tank is possibly close..

 

The "miles to empty" calculation is a crap-shoot. Can depend on whether you parked your truck on a slope--up or down--when you restarted it. Also uses the most recent consumption data (and I'm not sure over what time frame) to do the calculation, so if you've been hypermiling recently, it'll give you a bigger guesstimate than if you've been lead-footing it or towing. Just figure it makes sense to fill-up within a short time after the light comes on. The standard mantra about running your tank low on fuel is that you can overheat the pump. No clue if that's true or if it's an internet myth that's been passed around so much it's become a truth, but unless you're driving in west Texas or places in UT, NV or some gawd-forsaken wasteland, just fill it.

 

I love the 36 gallon tank 👍
My last fill told me I had 788 miles of available fuel on board. 3.5 with 3.55.
I too question the other end of the scale though. I’ve yet to put more than 31 gallons of fuel in it, even when running the tank down to 50 miles remaining.