Last truck was a 01 King Ranch SuperCrew 4.6, 3.55 ratio. Averaged around 14.5 in all types of driving.

New truck, 05 King Ranch SuperCrew 5.4, 3.55 ratio right at 14 to 14.5 with 9700 miles.

Really not all that much difference in mileage. The 05 is much more powerful and I also think the 05 is heavier. Just the price of gas is MUCH more.

 

New style 2004 Scab 5.4L 3:55 4x4 Full Leer Cap @ 9000 miles.
Fuel 87 oct. Stock!!! No engine/exhaust/tire mods...

Calling all fellow 5.4L!!! Everyone that did the exhaust/intake mods... Did you see a MPG increase and how much do think it helped good or bad.

By increasing 1 mpg in my case I can save $100 each year. That’s about 5-year pay back to get an intake/exhaust mod.

My overall mileage started at 15 mpg from day one off the lot.

It creped up little by little throughout the New England winter to avg 16+mpg.

Last couple of fill ups on summer gas yielded 17.2mpg!!!

This is about 40% Highway @80mph, 60% stop go city/rural.

I don't want anyone calling BS. By saying so is calling me a liar. I've gauged every fill up in the last 9000 miles in different no name gas stations. If your truck gets less I It would appear it varies a bit truck to truck. From what I've read the 5.4 can get equal if not better MPG than some of the 4.6's.
I do baby it a bit in the city stop-go but when I get on the open road...

 

FX4 2004 F150 5.4L 3V 35K miles no mods 100% HW driving at 75MPH 3 pasangers, a lot of camping stuff on rear cover with a tarp and a very easy on gas pedal

I get 19 MPG Driving from El Paso Tx. to Monterey Mexico with Sams Gasoline and clean Mobil Syn 0W20


Maybe unload can get 20

 

4.6 STX 4x4. jsut went on a trip of about 700 miles. 19 on the interstate, and about 16.5 in the city, and i have a very heavy foot, especially when it runs alot better down in omaha cuz of the air

 

OK, I've got 05' supercrew with the 5.4 L, tow package, 3.55 gears and right now I average about 15.5 mpg mixed driving, mostly light city driving, and short freeway sprint, about 2 miles I guess. Strait hwy I've seen as good as 19.3, very light foot, heavier foot yields about 17.6 strait freeway. I'm pretty happy with my 5.4 and I didn't get the 4.6 because I figured fuel economy would be about the same. I would expect the 4.6 to get better hwy mileage than the 5.4, but worse city mileage in comparison.

 

Had a 2004 XLT 4.6 Screw 4x2 and got about 14 in town and 20.5 on the freeway.
Traded it in with 21,000 miles For my 2004 Lariat 4x4 Screw that is by no means stock and it gets about 12 in town and 17 on the
freeway,
And i Drive all my Trucks like i stole em lol