I was without a car for 5 years. Rode an XLH in Chicago and walked.
Now about 2300 miles on new F150 2.7 RCLB. I am getting great not yet documented here MPG. I always check my MPG, since I was 16. According to my slow auto feed fillups so far, the F150 mileage calculation is about 0.2 high. I have checked every fill.
The computer says 22.1 MPG so far. Rolling around rural and slow Interstates I see intermittent 25 MPG and a lot of close to 24.
I drive real easy and plan 10 cars ahead. I roll to stops but will jump on it if necessary.
This is the quickest truck I have ever driven.
My tires are over inflated according to the sensors at 39 PSI from the factory. I bet the dealer never checked pressure. I will put at 36 tomorrow.
I've got an F150 with the same power train combination. Mine's a 2015. Pickups are very variable due to all the configurations, gearing, drive combinations, and even tire/wheel sizes as compared to cars. Mine happens to be the smallest and nearly the lightest available with the highest gearing @ 3.31 rear axle ratio. Mine also is not the work truck but has only the very lowest option package; meaning it's nearly as light as one can buy in any full size truck. Mine also has the chrome bumper package, which means it's got aluminum wheels instead of steel, so I'm guessing that my truck is at or near the std cab, short bed curb weight listed at their website, which is at or about 4168. For 2016, the weight dropped for this same truck about 30 lbs, so I'm assuming that Ford replaced some more steel with aluminum between those two years, but I haven't looked to see if there was a change for 2017, but I doubt it.
In 2018, the 2.7 is going to be redone. It's going to get dual fuel injection, probably new turbos, better performance (as if it needs it), and most-significantly, it's going to get mated to the new 10 speed transmission, and it'll likely get rated at slightly higher mpg, even if its just on paper. Ford says it's going to be more durable and robust, which is a little concerning, however, I've got 21,000 miles with no hiccups.
You're driving this power train the right way for great mpg. A turbo-charged, DI gas engine has to be babied to get great mpg, because spooling the turbos will be more detrimental to gas mileage than otherwise, equally-equipped, naturally-aspired engine. It's likely then, that drivers who tow frequently, get worse mpg with the 2.7-powered truck than even the V8; but for people like me who use my truck for a truck occasionally and use it for basic transportation most of the time, and who like turbo charged gas engines for their refinement (low-end torque) and not so much due to their sportiness when pushing them hard, it is a good, lower-than-diesel-cost choice.
I have got amazing mpg from this truck with this power train. The EPA estimate on mine is 19 city, 26 hwy, and 22 combined. I have measured all but about 2 tank fulls since I've owned the truck; use it to commute in a rural area and to drive to a nearby town usually every weekend once or twice; but all rural with low to medium traffic; all requires state highway jaunts as I live 9 miles form the nearest town or red light. My mpg is averaging 24.1 over the last ten tanks on Fuelly. Mine is very consistent, probably because I do alot of the same kind of driving. I find it hard to achieve the highway estimate; only if it's very warm outside and only if I drive 65, and only if it's not very windy or raining, and the trips are quite long, can I achieve the estimated 26. However, 25.5 on the highway for me, is quite normal. City driving is another matter. The estimate is 19. I think that my city-only real-world mpg, is more like 20. That's amazing for a full size truck; and overall, I have hadfour full-size trucks in my life; all Ford (1989 with I6; 1997 with 4.6V8; and 1999 4.2V6; and drive a 2010 4.6V8 at work), and even though Ford has been raked over the coals for supposedly exaggerating mpg for all Ecoboost-powered vehicles, I find that this truck, with this engine, driving the way you and I drive, likely can come the closest to meeting the EPA estimates of any truck/engine they've built since the 80s (but that was at 55 mph as the hwy estimate).
As for the trip meter error, mine is much, much greater, than what you've found so far, but that there is a good chance they've changed the software or sensors for calculating the mpg, since mine is so bad. Mine has a huge error in the "gallons used" calculation, and therefore, it will average 1.3-1.9 optimistic on it's mpg estimate. In other words, if my truck shows 26.5 when I fill up, it'll likely be somewhere between 24.6 and 25.2 in reality, but the error is not consistent; and so I don't really use it much.
But mine has another error in regards to the trip meter, yet it's in the other direction. The miles driven indicated on the trip meter and odometer, checking against a couple of GPSs several times, under reports miles driven by approximately 1.8%, which is good for warranty purposes, and for mpg calculations. So in order to be conservative, before I divide miles driven by gallons pumped to fillup, I multiply my miles driven from the previous tank by 1.015 accounting for a 1.5% pessimistic odometer error.
My tire pressure recommendation is 36. Right now, since it's warming up outside, I'm running 38-39 average cold pressure in the mornings with Michelin LTX 24570R-17s, but am waiting just another week or so when I know that we're through with all the cold snaps, and then I'll take out a couple psi pressure from my tires. You should be fine. The factory likely filled the tires when the air temp was colder and now it's warmed up. It's better to be a little high than low for safety, tire life, and mpg, but if you let it get too high, it could be dangerous because it's easier to blow out if you hit something.