Originally Posted by acdii

I can see that happening. If the road is flat enough, few stop lights, and speeds if 45 or lower. When traveling to work there is a small section that it 30-45 MPH and thats where I see my summary jump up to max, so for about 18 minutes of my hour 20 minute drive I exceed the top of the estimate. All the rest of the drive it hovers right around the 21 mark.

Ford will not publicly admit it, but they do say the EB gets best performance and economy using premium fuel. I was told this BY FORD when I questioned the poor MPG the 2012 EB I had was getting compared to the Flex I traded in for it. I was getting between 21 and 24 MPG in my Ecoboost Flex, but barely hit 17 driving it on the same roads in the same conditions and driven the same way. They said to use Premium to get better economy. I did not believe them, but tried it anyway and they were right. The EB in the Flex is not the same EB in the F150, only the displacement is the same. I don't even think they use the same block. The one in the Flex uses a different head with different cam design, so it runs perfectly well on 87 Octane with top economy, where the EB in the F150 needs higher octane to get better economy. I have had 2 Flex and one MKT, all with AWD Ecoboost, and all three were consistently in the 20's, but the 2012 F150 4x4 and my current 2014 RWD are in the 17-19 range on 87. I switched to premium after 5000 miles on the 14, and enjoy 20+ all the time(unless my right foot gets happy).

Originally Posted by Mach 1

All my FE is at 55-65mph..


When I got my 27mpg and 640mpt, I had the truck loaded and bed loaded with almost 2000lbs..they say you are good .1mpg per 100lbs.


So with that I would hav got 2 more mpg on top of 27mpg, or right at 29mpg, at 55-65mpg..it was a very flat NE Texas back highway...No AC that day...

Originally Posted by Mach 1

acdii, you understand it..I wish someone would have told me about the premium Vs. RUG..it just plain likes it, but better power and FE..


Hey, did you ever own a VW diesel..I remember someone on the board over there by your screen name?

Originally Posted by Blown F-150

It is possible that the extra 1000lbs of the truck (if you're talking a 4x4 Supercrew) is also a factor in the MPG difference from the Flex.

I also see an improvement running 94 or even 91 compared to 87 octane, especially when it's hot out.

Originally Posted by twowinns

i haven't been able to get better than 14 mpg since i've had the truck (11 months and 7700 miles). The only thing i've done to change it from stock was slightly larger tires - from 275/55/20 to 275/60/20 - bf goodrich all-terrain ko's).

I knew the change in tires would affect the mileage, but i thought it would just be 1 to 2 mpg. I haven't been able to get the computer re-flashed to recognize the larger tires, so the 14 mpg i'm getting should be a little higher - since i'm actually driving more miles than with the smaller tires - right?

Should i get the system re-flashed to account for the new tires, before i take it to the dealer to have them check out the engine?

Originally Posted by dawg76truck

i have a 2013 ecoboost 3.5l v6, never gotten over 14.8mpg,, have any answers? Thanks.

Originally Posted by Topgearloader

Answer - your truck needs a quick tune up for the usual eco problems. Once you do those, you will get some increased mpg.