I had a 96 bronco with the 5.8 drive it the same way as the 5.4 in my fx4 super crew & they get the same. I get 13.5 in town & not much better on the highway. I would think 10 years of tech they would be better other than just power. I do live in MI were winter makes them bad, but I hope it will get better.

 

I have never owned a Ford truck that got anything but 13MPG, 1997, 2002 and 2006 F150, 1998 Expedition...around town and maybe 16MPG on the highway.

 

I have an 01 4x4 Supercrew w/ a 5.4L, 3" bodylift, 35" tires and a 3.55 gear ratio and my best is 11mpg normal driving. I may hit 12/12.5 or so if it was an all highway drive on that tank of gas

 

my dads 05 supercrew with level kit, taller tires, intake, superchips, magnaflow gets about 14 in city/17.5 highway

 

I have a 2005 extended cab witht he 5.4 motor and I get about 14.5 in mixed driving. I keep my foot in the injectors most of the time if you know what I mean.

 

you should switch to a lower gear and you might get back some mileage go with 4.10's

 

As in my SIG... about

11.5 in 4x4
14.5 mixed drive
16.5 highway

 

I get 17-18 in mixed driving with mine. I am happy with it. But then I drive like a little old grandpa.... I could get 9 mpg if I drove it like my focus

 

I drive mine pretty hard, get 16.5 to 17 around town, 19.2 to 19.5 on the highway. Close to the same on the Expedition.

 

yeh i was gettin bad milage.. then i changed out plugs and put my BBK 75mm on now i went from 15 highway to 22 highway and 18 city

 

you are not alone... Mine is only getting about 15 and I have babied the hell out of my driving lately!! I live in Kansas and it is always windy though...

 

Yeah I know I need to do that I am just lazy and dont want to drop 500 bucks into gears. I have all of the stuff to do it excpet the ring&pinion gears for each axle. I was actually thinking of going to a 4.56 beacuse I do alot of intown driving mostly. I've seen alot of post where that ratio seems to be the most used for trucks similar to mine. I also called 4wheelparts and talked to a driveline tech there and the 4.56's is what he suggested to me to. But I think the 4.10 will probably be the optimal for the fuel milage savings.

 

Just curious, why would a stepper gear like a 4.10 get you better gas mileage than a 3.55?
I can see the logic for driving around town, stop and go, but for alot of highway driving it would not be good correct?

 

Well, you're driving about 5900lbs. around town. I do too. Never gonna get good mileage. Although, I don't do much worse than my old SC 4.6. Get about 12.4 in town and up to 19 on long highway trips (70+). Lariat SC, 4X4, 3.73's.

 

I drive a 05' F150 and i get 12-13 in the city and 15-16 on the highway.
Tech has nothing to do with saving fuel the way fuel is combusted in the engine and everything hasnt changed because there just isnt a new excitting way to make the chain reaction or fuel efficiency in the engine.
You can change other things that might help out.