99 Super cab 5.4 6.5' bed 199,000 miles

I usually get about 300-330 per 25gallon tank. Highway driving I remember getting 370 once in the countless tanks I've filled up over the past 8 yrs.

 

You either have:

1. No idea how to check MPG; or

2. A neighbor siphoning your gas; or

3. A serious leak in your fuel system.

140 miles on 25 gallons is 5.6 MPG. A 600 HP Lightning gets better mileage than that...

 

Your "Low Fuel" light goes out!. I haven't seen mine go out since 2006. I am so sick of seeing that little yellow sign that it was taped over. Merry Christmas & Happy New Year

 

i know how to check mpg 140/25=5.6, no leaks what so ever, and if a 600hp lightning can get better gas mileage then me, i wanna know how, ive checked damn near everything, gas mileage sucks, but i love the truck:o

 

Dont worry, my gas mileage sucks also, and also, i love the truck.
My '01 5.4 short bed is lucky if it gets 300 to the 25g tank, but then again, im not light on the pedal

 

i've got a 2005 lariat supercab with the triton 5.4. i get 470mi. til empty. i think i have a 34 gal. tank

 

I would bet there is something else at play here:

1. Are you running taller than stock tires ?

2. Are you running a different rear-end gear than stock ?

If yes to either, has the computer been flashed with the correct data to work with the changes ?

Try this:

Fill up, until you can't get another drop in the tank. Drive on the interstate for a known distance (from a map, not your odometer). Fill up until you can't get another drop in the tank and do the math. (I think you need to drive at least 100 miles for this to have any chance of being reasonably accurate).

Then, let us know what you find...

FWIW - My Lightning makes 425/520 at the wheels and I recently pulled a 2500lb. trailer for 700 miles. Kept it at 65 or so and it got 12.5 MPG consistently, even in the hills / mountains of northern Georgia & Tennessee. My usual MPG is 14.5 - 16, depending on the highway / city ratio.

 

I just took a 400+ mile trip and got 18.1 mpg doing between 60-65 mph, 2004 f150 supercrew 5.4l all stock, and I used the 4 wheel drive approx. half of the time.

 

285/75r16's , rear end is stock, ive re set the computer a few times when cleaning maf, just to see if that did anything, and it didnt

 

Your math is off... You divide the miles driven by gallons put in the tank, not gallons the tank can hold (25 gallons!).

 

These numbers are spot on for me as well. I usually try and keep track of my milage. I really wish I had all highway miles as the extra 35-40 miles per tank does add up.

 

Can you still get the 35 gal. tank on the 08's?

 

k, so i did that wrong, i ment to say the ammount of fuel the gas pump tells me i put in the tank, not 25 gallons. But still, on average i put in 22-23 gallons, and that still only equals out to be 6.2 mpg. the more i think about it, the more i dont care.

 

to get 5.6 mpgout of a f150 i bet his fuel press reg is f**K my 89 ford f-150 did that but it would only go liike 100km so 60 mi on 15 gallons it was reallly cold that week so i just keep putting fuel in when it got back up to - 10 c i put a fuel press reg on went back to 18 mpg from like 4mpg haha the rig i drive get 5 to 6 mpg my f 150 was harder than a mack lol. thats bad

 

Atta boy