wow 13.9 is all i get and thats down hill with a tail wind lol
you bought a truck not a little fuel cell toyota with wheels and if you get hit your dead. your now in the 5 star crash rated best selling (33 pulse years) truck!

 

That's about the best I could get with my FX4...I stay right around 14...sucks but damn I love my truck !!!

 

I just did a 140 mile road trip today with mixed speeds but mostly highway with some heavy traffic at some spots. For the most part my speeds were 65 to 75 on the highway and got on it a few times to pass and I averaged 18.1. I have a 4.6L 3V SCREW 4x4 3.55 rear and 6.5 bed with 9300 miles on it.

 

Well, my son has a 2006 F-150 Crew 4X4 Lariat with 3.73s and oversized 20" tires and he gets 15, so I was expecting the six-speed auto, higher (numerically) axle, and 17" tires would beat that by a little more than 3/4mpg. I would settle for 17 as my 6.0 diesel was just under that when I drove it.

 

I agree. The 2010s are supposed to be much beter than the older 5.4s. My problem is solved though. The F-150 is no more. It will be missed though.

 

My 2008 F150 Super crew FX4 with 5.4 and 3.55 rear got between 13-15 but the 2010 same engine model with a 3..73 rear and the new six speed gets between 15-18. 2008 had Banks Ram Air, hypertech power programmer and cat back exhaust with magna flow muffler, 2010 just has stock intake and and magnaflow cat back exhaust. I think it may do better with the cold air intake when I add that, not sure which brand I am going to use this time. Banks was good but I don't see an application for the 2010 yet on it.

 

So what did u buy for a replacement??

 

The first tank netted a 15.3 mpg. Each new tank increased the mileage a tenth or two. Now at 10K miles I average ~18 mph. The cool fall weather has increased mileage to ~18.7.
So I would say your mileage is about on par.

5.4 3.55 LS 4X4 Supercab (18 in tires)

 

Another car and I'll buy a "work/play" truck later this year or next.

 

Exactly right, driving 500 miles on the highway with a brand new engine is NOT recommended as the pistons need to experience a wide range of RPMs to correctly seat during the break-in process. Don't worry though, just punch it around town, don't red-line it, but make sure the first 2,000 miles or so have a good variation of RPMs.

These new engines don't need much in the way of breaking in. However, what I just described is the way I broke my engine in, as well as getting my first oil change at 3,000.

I recently passed 18,500 miles on the truck coming back from a long trip. I averaged 20.3 MPG, this is usual for me (on the highway I mean). Like Wes28376 said, you'll get better MPG if you don't use the cruise control, at least on these 2010's.

 

once you cross about 65 say goodbye to fuel mileage. I drove my grandpas 2010 4x4 crewcab home from the dealership. set the cruise on about 62 and the read out from there to home (35mile trip) it read 19.5 mpg. Its a truck....it has been averaging 14 to 15, its the farm truck so not a lot of highway miles.