Haha that's true! However if 4.10's were available, I would have them! The sales man tied to talk me out of them, I told him I didn't care if raw fuel ran out of the tail pipe, as long as it could get up and go when I wanted it to ! True story lol

 

Alot of complaints on here I see about the mpg digital calculations being off, and reading high.

I'm not seeing that issue at all on mine. In fact it's pretty damn accurate. I'm on my second tank now. I was a little under half a tank when I filled up.

Truck said I was getting 19.4 mpg. I put 13.7 gallons in the truck and had gone 273 miles.

Manual calculations showed I was actually getting 19.9 mpg.

So as you can see, in my case it was pretty accurate, actually underestimated by 1/2 a mpg. I can live with that.

Btw , at the time of fillup, this new truck had 293 miles on the odometer. Mileage is only going to get better!

 

This is the first time I've ever heard anyone say the computer overestimated mpg compared to hand calculations. Maybe it does happen!

 

My 2015 Ecoboost is always a bit optimistic. If it says I burned 20 gallons it usually takes 21 or so to fill it up. We are getting mid 18's normal driving and 13.5mpg towing our 27' Airstream.
That is about 1-2 MPG better than out 2012 Ecoboost got.

 

On my 2012 lariat litres used was the only reliable method of knowing when to go fill up as my DTE and need fuel warning light where the ****s. There where times when the light came on at 36km til empty. Then it would go out and sometimes it would come on at 150km til empty. I bought an App and tracked fuel economy. when I fuelled up it was always within 1-2 litres on a complete fill. I knew I avg 6.86 km/ litre so at 126 litres burned I knew I could travel 10 X 6.86 or rounded down to 50 km to be safe. How's that for math.
Just did my second fill with the 2016. First was following the dealership going to get it from another lot. Lots of idle time I'm assuming as the calculation read 30.2L / 100km. Last fill was 15.4L/100km. I do miss litres used as the other methods sucked. Will see with this one.

 

My 2011 F150 with the 5.0 had a very accurate trip computer on it. Not sure what Ford changed on the 2015/2016 models...

 

This-my previous gen truck was pretty much dead pn but my 15 is off by at least a couple of gallons every fillup.

 

I've been keeping all my receipts since I bought my truck and I use an app to track my fuel mileage. 95xx miles on my truck and 16 fillups.

Every single one is 1.5-2 mpg lower then what the truck computer is calculating. Computer always says I'm getting around 17-18 mpg. Actual is always 15-16 with overall lifetime of 16.2

 

They definitely do not. I can sit there and watch it drop. That said, I do not believe they account for the extra fuel that is used when the engine is cold. I think the gallons used references the fuel maps but until the engine reaches operating temperature, it runs rich. That is the only explanation I have come up with as to why the mpg and gallons used are off by more in the winter than in the summer.

OP: Gallons used could be 1.09 and it will still read 1.0. With such a small sample size, the variance can be huge. 17.4 miles and 1.00 gallons used would obviously be 17.4 mpg but 17.4 miles and 1.09 gallons used would be 15.9mpg.

Nothing. My 2011 was the same as my 2015 is. The colder the weather the farther off the numbers.

Your understanding of how it works and mine are very different. I've sat in my truck with it running while waiting for my daughter's bus on a cold day and watched the mpg drop lower and lower. I've seen it lower when getting into the truck than it was the night before after letting it warm up for 10+ minutes in the morning. Obviously it is much more noticeable when you have fewer miles driven to impact the calculation. If I fill up on the way home, I've only got 10 miles on the tank. Idling for 15 minutes can make a huge difference.

 

Idle time is only calculated by the computer IF the key is in the ignition. When you use remote start the computer IS NOT calculating idle time into MPG equation. So if you use your remote start & let it & idle for 10-15 minutes, the fuel burned is not calculated by the computer. If you don't believe me, write down what your current MPG is. Then use your remote start & let it run for 15-30 minutes, or whatever the max time is. When it times out & shuts off, go put your key in the ignition & start it up, your MPG will be exactly the same.....it won't change at all because your computer doesn't calculate idle time when using the remote start function.