Hello, just purchased a new Lariat scab 2.7 4x4 3.55. Absolutely love everything about the truck, drove it home yesterday 600 miles and even my wife, who hated full sized trucks, loved driving it.

Not going to gripe about the fuel mileage, but I did notice the fuel totalizer is way off. I filled up in OH until it was dribbling out of the filler neck and reset the trip odometer. Get to NJ and it says 408 miles, 20.3 gallons consumed and 20.1 MPG. I fill up and it takes 21.5 gallons. That's a huge error. Also means MPG was really 19.0 MPG. I'll try a few more comparisons to see if this was an aberration. Even 19.0 isn't bad, speed was 75-80 MPH the whole trip, except where we couldn't go that fast which wasn't often. But the highest I can coax out of the readout is just over 21 MPG at 62 MPH or so. If the totalizer is off, that means the max MPG is 20.

Like I said, a few more trials to validate. FWIW, I've owned a lot of cars and not seen the MPG increase on any of them after 'break-in'. Time will tell.

 

you really should only be filling to the first click. Filling the neck presents a potential for a fire hazard and puts strain on the evap system.

Aside from that, the computer has to make some assumptions. It read 5% off on the fuel used and 5% off on the actual mileage. That's actually pretty damn good IMO, considering things like an allowable 4% variance in speedometer calibration and such.

 

May be good for you, I've got a bunch of other vehicles with totalizers and they are spot on.

Speedometer is dead on, verified with portable GPS, which is refreshing since so many cars are off to the low side on purpose.

 

this has been discussed at lengths. some seem more accurate than others, but in general, you shouldn't expect the gallons used on your truck display to match exactly what the pump says.
and x2 on not making your truck puke gas

 

my old 2012 and my new 2015 both show that the truck takes about 1.5-2 gallons more to actually fill it than the truck thinks it used at every fillup. A few times it was as high as 2.75 gallons more that what the truck said it used. I had 27k on the 2012 and 4k on the 2015 so far

 

Mine is the same way. It always shows about 1.2 gallons off what the pump says. Makes me wonder if Ford is doing this to make their MPG numbers look better than they really are...

 

no, you think ?? It's probably due to the way fuel is "measured" somewhere in the system, but I bet that if the error was on the other side (ie. displaying 1-2 mpg lower than actual) they would have found a way to fix it!

 

Thing is there should be a an easy way to calibrate it. As simple as entering how many gallons were actually used after filling up.

 

I've always found that 36 gallon tanks have the biggest error. My on board mpg computer & gallons used is always off by about 1 mpg & about 2 gallons to the good consumed. But my miles to empty is always correct for some reason.

 

Same here, but it was pretty close on my 2013 which also had a 36 gallon tank.