'06, F150, 4X4, 5.4 Automatic, 3.73 differential. New air cleaner. 5/20 semi-syn.
Round trip. Spokane to Seattle. Approx 300 miles
Westbound. Cruise to 65mph. 15.1 mpg
Eastbound. Cruise to 70 mph. 13.6. mpg
85 miles Seattle in town miles. 10.1 mpg
My previous '95 had the old 300 cu. in. I-6 and I loved it. But it was plenty thirsty. 15 mpg at the best. I was hoping that the 5.4 might do better.
Is this what most folks are seeing? Or, might I have a problem?

 

That's sounds about average for these trucks. I think I could drive mine off a cliff and shut the engine off on the way down and it would still average 12.7 mpg, does everywhere else no matter how you drive it.

 

If I drive mine like grandma and keep it at/under 2000 RPM's while getting up to speed I normally get between 16-18mpg.

The last few months I've been driving it "normal" getting it up to 2500 RPMs and occasionally 3k when I'm really "getting into it" and my mileage has gone down to 13-15. Winter blend is also here so that causes a drop in MPG.

 

Same here. I averaged 18 MPG from Florida to MI one time. Pulling a trailer the same trip back I got 10 LOL

But yeah im a bit down for the winter too as well

 

 

What a dee eye see kay....

 

i have an 04 screw fx4 with 3.73 and 33 inch mud terrains and on i5 between seattle and portland keeping it under 2k i will get 15 mpg. thats on 87 that the manual requires and factory tune. im going to start trying ethanol free next tank i think

 

I have an 07 FX2 with the 5.4 3:55 gears and see 17.8-18.5 every week hi-way 10 mi 4-lane 70-75 and 25 mi 2-lane 60mph. hand calculated, I have gotten as high as 19.8 all hiway on a trip. I'm satisfied...

 

To be on cruise, stock, 3.73s, pushing 70 .... it's maybe a hair low but in the ball park.

I can do better than cruise with my right foot by a couple MPGs anyway and with stock tires (275/55-20) and 3.55 gearing I got 18.5 or so on the open road easy. With the SC FP1865 on 87 perf setting I get 20-20.5 no sweat and on one 300 mile leg from Conyers up into NC and over to I-77 and up towards Hillsville I got right at 21 mpg last January .... but not with cruise control.

Cruise does not anticipate slow downs or hills or grades, it does whatever it has to to maintain as close as possible the set speed and that's NOT a best recipe for good mileage. I rarely use cruise control though all my vehicles have it, even my '77 has add on cruise.

Now, when I was working as a Trooper and was just cruising, I used cruise if the car had it as it wasn't my gas. Likewise when I hit the highway to go to another store in my current PT gig at AAP as MPP.

 

I've got a 07 FX4 that's pretty much stock, and my highway average is 18 mpg. The only thing that I have done differently is run fully synthetic oil and keep my K&N filter cleaned and oiled. I'm satisfied.

 

Traded a 2010 with 5.4L 3.55, that consistently gave me 19.6 Avg. Mostly highway though.
My driving habits are to get maximum MPG, but without driving like a 90 year old.

 

I average around 16 mpg with my 05 5.4. It has the 3.55 gears and a 4x2 trurck. I drive 54 miles one way to work and its mostly interstate with only 10 miles of the drive city driving. This is with the original plugs in it yet and they have 110k on them and counting. Also I set the cruise at 75 so 16mpg ain't too bad considering.

 

What you're getting is normal. The whole reason why I let mine go and now drive a small commutter car.

 

I have almost the same setup (2010 FX-4, 5.4, 3.73, etc) and I do a bit better. About 14-15 in town, ~20.4 MPG at 55 and about 18.6 MPG at 70 MPH. Drafting (even at a distance) makes a big difference (+2 MPG). But I have a six speed auto and I drive in Florida (flat). I've found that the acceleration rate from dead stops also makes a BIG difference.

 

2004 fx4 5.4 getting 18.4mpg mixed driving, 20.3 mpg highway. Edge programmer level one helps a little bit.