10-14 mpg with 2010 fx4

[Jax]

Hi guys, I just bought my first F150 a couple months ago and I absolutely love it. My only concern is the more I read up on it, the more I think the 10-14 mpg I am currently getting may suggest there is an issue with the truck. I have a 2010 fx4 s/crew w heavy duty tow pkg, 3.73 gears, 5.4L flex fuel engine. The truck has 95,000 km on it.

I have done the usual, checked the air filter, tire pressure, etc. The truck runs perfect other than the mileage. I don't have a lead foot and I drive about 65%hwy, 35% city and get around 11 mpg. The thing that really concerned me was after about a month of driving and getting 11ish mpg I took it on a 1100km road trip. On that trip I couldn't even hit 14mpg at 65mph.

I realize it's winter and I am not expecting great mileage but just wondering if someone has had a similar experience? Was it resolved? I wouldn't care if it cost $200 to fill I'd still drive it so that's not an issue. Just want to make sure I'm not missing something here. Any Canadian daily drivers who can comment on winter fuel mileage expectations? Any help would be appreciated! Thanks.

[Jersey_Joe]

I have an 03 5.4. New 5.4. Lol. I have alot of mods on my truck. But with a few upgrades u can get 15-17. I get 18 steady and 522 hp. U have a nice truck man. Plenty to put on that puppy

[RhinoZ24]

Have you changed the fuel filter or know if it's been changed lately? May be time for new spark plugs as well. When was the oil last changed? Also try running some fuel system cleaner through it, that might help a bit. Also, I bought my 05 used and was getting low mileage, around 11-12, was told it had a new air filter but I checked it out anyways. The filter was new, but I looked inside the air box in front of the filter and discovered about 3 or 4 small leaves. After taking them out my mileage went up to around 13-14. That's mostly city too. So check out you're air box because you might have something restricting the flow like I did.

[Jax]

Hey guys thanks for the tips so far. After carefully monitoring my mileage over the last couple of months I have been able to determine that I am getting the gas mileage expected when running E85 (even though I am not!). I am using www.fueleconomy.gov as a basis for expected mileage. I have used this site as a bench mark for all the past vehicles I have owned and it's been really close. Is it possible I have an issue with the sensor which determines if I have E85 or reg gas in the truck? Has anyone had this before? I have read a few posts of ppl with issues but it usually involves error codes. FYI a weekend trip to the cabin this weekend and got 13.6mpg (all hwy).