Note that if you haven’t calibrated the mpg setting your true mileage it likely less than 20.
They may not all be wrong, but the two I have calibrated so far, using the Engineering Test Mode, were indeed wrong. My 2018 SCREW 802A was consistently more than 1 MPG on the high side indicated, sometimes up to a tad over 2 MPG. Last year on a ~5950 mile trip the actual calculated MPG was 15.91 and the indicated MPG was 17.2 (thread here
https://www.fordraptorforum.com/thr...ance-trip-report-with-mpg.63372/#post-1289332 )
After using the ETM to calibrate the the readings I don't think I have ever seen it be more than 0.2, and normally more like 0.1, off of real mileage. It is simply accurate now. I checked it the first 20 or 30 tanks after calibration, now I just take it as gospel and only calculate for comparison once a month or so.
My typical over the road mileage, if I am 5-10 over the speed limit, is 15-16 MPG. If I keep my foot out of it on accelerations and do roughly the speed limits I get more along the lines of 17-18, the best I have seen for an entire tank of gas is a bit over 20 MPG, but that was specific terrain (almost all down hill for hundreds of miles) for the entire tank. If I drive it how I want to on a daily basis, enjoying the loud pedal a bit, I get 14-16, with just under 15 being very common at fill-up. In my log book I have a running average of all the mileage I have gotten to date, at 34000 miles in a bit over 18 months of driving I am at 15.2 MPG.
Considering what it is, a relativity high power, sport oriented, lifted, crew cab, 4x4, running 35" off road tires, I think it does just fine on mileage. And it consistently gets better MPG than my unlifted 2018 FOrd F150 4x4 single cab work truck with the V8 and less HP or torque. If I wanted high MPG I would drive Tesla or a hybrid of some kind.
T!