Once you get above 70, 16 is about all you're gonna get, mine is the same way. I slowed down to 67 and I get 18+. Remember, when the epa tests the MPG highway it's at 60mph not 75 or 80.

Mark

Tom, you and I are near each other, driving same kinds of roads it seems. This Ecoboost mpg is disappointing! I get 18 - 18.4 on interstate doing 73 in my '02 5.4 with CFO, hound, all kinds of mess strewn about in me truck, Supercrew, 3.55 rear end. Man, with Ecoboost, I'd sure want at least 20 highway.

Quick update.
After getting reprogrammed I'm getting 16.8 mpg average while driving a little harder and NOT being a granny. So there was an improvement.
Its amazing how much those little numbers get into your head.

The Ecoboost is a awesome LITTLE motor. At only 217 cu. inches, and when pushing these comparatively heavy trucks, it really sucks the fuel when any load is thrown at it, like head-winds, side-winds, incline in the road etc. BUT when you need the power it never disappoints!!! As most have said, once you start above 60-65 mph, it's mpg suffers. I stressed hard over the same thing as you, was thinking of trading it in for a 6.7, but then did a little calculating. Honest numbers for OVERALL mpg at maybe a 4 mpg increase between a 6.7 and an Ecoboost means barely $600 a year, meaning it would take 6 - 7 years to break even on the trade-in.

I came to the conclusion that it's such a GREAT truck, that now, the mpg is no big deal, and driving this wonderful little truck is such a joy (FX4 loaded) and when you NEED the power it's there and combined with it's classiness that I am content. When I feel the need to see the mpg that was advertised, I re-set the odometer, drive 60 - 65 mpg, and walla! 22- 24 mpg. :-jamming

Enjoy your truck!:-X22

The cost differential would depend on how many miles you average annually. 4mpg is a huge difference for those who put high mileage number on their trucks. Also, around my area diesel is substantially more expensive than regular.

I'm amazed that that small an engine that has that much torque available at highway cruising rpm can only manage the figures I've just read in the above posts.

get the truck warmed up then get on the highway. Get up to 60 mph. Set the cruise. Reset the fuel economy, drive about 20 miles. If you don't get 19 or better you have a problem.
My 2011 SCAB with max tow and 3.73 would get 20-21 mpg, my new 2013 King Ranch SCREW with max tow and 3.73's with the 6.5' bed (and it weighs nearly 900 lbs more than my old truck) will get 19-20mpg

If you are bucking a headwind take off from 1-3 mpg, if its pushing you add 1-3 mpg. If it's cold take off about 2 mpg, if it's really hot take off 1 mpg or so

My truck has been from Wyoming to Arizona to Kansas several times. I see pretty large differences in regional fuel MPGs. I think that this motor is pretty sensitive to what you're feeding it. Mine likes non-ethanol fuel best. Driving like a granny and staying out of boost nets 20 mpg easy. Driving like I want to with the turbos spooled up constantly drops me down to 15 easy. I always run 87 or 88 octane. Bottom line is, there isn't another gas truck out there that is capable of 20 mpg and can still hook up to my 11,000 lb. toy hauler when I want to go to the mountains. I'm not disappointed.

Doing that for about 7 miles nets me 21.5.

Don't take this thread as a complaint. I love my truck. Its the strongest and most luxurious vehicle I've ever been in.
I just wanted to compare and check to make sure there was not a problem with it that was causing the discrepancy.

If you are getting 21.5mpg then you are doing fine.

Short trips, starting and stopping, heavy foot, hills and the wind all lower it. As does driving with a cold engine. Take about 10 miles for them to warm up to maximum efficiency- unfortunately most of my driving is less than 10 miles.

Enjoy your truck

There are just TOO MANY factors involved with MPG in these trucks. I drive RELIGIOUSLY at 65 mph in cruise control every single day to work and back. Some days the mpg is around 18 to work and this past morning it was 20.8 coming back from work. I have 3.73 gearing and during the trip back and forth to work there are hills and one 6% grade. Coming home I hit the 6% grade early and then it is mostly downhill from there to home...and obviously it is going uphill for the most part going to work until I get over that grade.

At this point if I have the time to drive 65 I do it to save on some fuel, if I don't it's back up to about 75 to get there a bit sooner. I drive 34 miles one way to work.

If you are fixated on MPG you are going to give yourself too much stress...my truck is right there at the rated MPG and that's all you can ask for. They are big trucks and do what they are asked to do when towing.

If you are getting consistently 18 or less on the freeway AT 65 MPH then yes there is a problem.