Street,

For the record, I also have a 2007 F-150 S/Crew 4x4 KR with 3.73 gears and my mileage is VERY close to the same as what you are seeing. I currently have about 6,000 km on the ODO (3,800 miles) and am hoping the combination of truck break-in and summer gas / weather will help mileage.

I, too, read about other's gas mileage claims and scratch my head in disbelief.

I am VERY easy on the gas pedal (very few quick starts, no more than 70 mph on the highway) and **** about calculating mileage (I keep track of every tank in a spreadsheet).

The BEST I have seen to this point is about 12-13 MPG in the city and about 16 MPG on the highway. This is hand calculated - my truck's average fuel economy calculator is a little optimistic on average.

By the way, I am 100% stock.

Hopefully this makes you feel better.

 

I bought my 07 Supercrew Lariat 5.4 4x4 20" wheels, it was getting about 15mpg. I immediately went to a SIDO with 3.5" tubing. Gas Mileage went up to 16.5mgp. I later installed a K&N Intake...my mileage went down to 13.5 - 14.5mpg. I do not know why and had I known that beforehand I may have spent the money on a different mod.

I'm also in Hawaii so there are a considerable amount of hills. I drive 60 miles daily. No more than 20 miles of Highway driving. My average speed is 50.

Next week my truck is going up 6" w/ 35 x 13.5 x 20's underneath. I'm expecting 11mpg. Pics soon.

 

It does. haha Thanks for the info guys.

I too will be lifting my very soon here, with 35x12.50x20's. And here I am complaining about mileage... haha

going from 15 around town to 12 is better than 12 to 10. Know what I mean?

 

Do you have a local dyno shop with a wideband O2 monitoring and eddy current loading? They would be able to see if how your air fuel ratios are under varying load conditions and rpms. With this data they will be able to tell if you need a custom tune or perhaps repairs.