just came back from the thunder in the valley motorcycle ralley in johnstown pa......had a 600 lb vmax in the bed of the truck and mostly highway miles but quite a few mountian miles as well.....did 21 mpg! had a little scare when the gas gauge dropped below a 1/4 tank when i was still about 50 or more miles to a planned fuel stop. ended up putting in 21 gallons (all that would fit), on 440 miles of travel. i have a 27 gallon tank. wish the gauge was more accurate. see ya!

 

That's awesome. I'm taking a trip to San Diego soon so I'll check mine on a long trip. Of course, I'll be haulin' a$$ across the desert with the A/C cranking so maybe I shouldn't check...

 

I got the same truck you got and I don't believe for a sec you got 21 mpg. maybe if it was down hill all the way. maybe you didn't get your tank all the way full. I don't know whats up but there is no way a extended cab Fx4 got 21 mpg especially with a 600 lb motorcycle in the back.

 

That's extraordinary with a load, unless you were puttering along five MPH under the speed limit with a tailwind. My 2WD Lariat with 3.55s will get 20-22 if I keep my foot out of it unloaded and drive 55-60 mph or so. Good deal nonetheless.

 

i kept it at or under 2k the hole trip.....why would i lie? you put up a post and someone has to be a jerk! oh well, jasonkola or whoever you are......folks, it can be done.....unless there is another problem or you just are constantly wailing on it. i guess you wouldn't believe i got 11 towing 7k?
i could see if i said i was getting 30! maybe i am being to sensitive tonight? long weekend.....probably wouldn't believe i can get 40-45mpg on my vmax either huh? oh well......hope someone out there appreciates info.....

 

You ain't talking to people who drive Hondas and Toyotas, we're all driving the same truck, driveline configurations aside, so we know what they're capable of, mileage wise, and what they aren't. If you got 21 mpg, great for you. My fuel economy sucks when loaded and is decent when unloaded.

 

I've seen others on here post that they get 21, 22 and one guy even boasted 23 MPG. I believe someone could get 21 MPG if they stayed off the throttle when taking off from a stop and getting up to speed on the highway.

 

I didn't mean to call you a liar just that the mpg claimed was unlikely. I figure either you didn't get your tank all the way full when you gased up to figure your milage. if there was still room for 3 or 4 gallons in your tank and the pump shut off. that would throw the gass milage figures off quite a bit. also if the trip was mostly down hill and or a tail wind. or a combination of all the above.

 

how about, i filled it till it held NO more......squeeking last few cents in to round up to a dollar amount.....then doing the same and actually having a little drip......so totally topped off to totally topped off.......i am no rocket scientist but i am not stupid......why not just fill it half way and say i got 42 then......is that better.....i am done now. don't get why if YOU can't do it then it CAN'T be done?

 

Filling the tank slam full after the cutoff isn't recommended anyhow, may saturate the charcoal EVAP canister.

 

jims94vmx, don't sweat it.
Some of the guys do get lousy mileage, and like the guys with the low A/C, they assume it's the truck design, etc. not their situation.
If a guys truck has the vibration, he swears you just don't notice it in your truck, you must have it,since he does. Check about a thousand posts...

That's just the way it goes.


On your mileage, I suspect you held it down around 55 a lot. Few of us do that.
I get fantastic mileage at 55. I don't do 55 much, as traffic around here holds about 75.
At 75 I can break 20 almost all the time. My truck is modded and lighter than yours, but at steady speed running, the weight of the truck, even adding the bike, makes almost no difference to your gas mileage.

It may kill it around town, up hills or on the onramp, but at cruise, an extra 1000 lbs won't cost you a half mile to a gallon.
Anyone can verify this in nothing flat, if they really care.


Wind resistance makes a huge difference, but all these F-150 bodies have almost the same wind coefficient.
Chris

 

You are so right on that Quintin, with the large flat tank, it's easy to overfill these trucks.
Three quick clicks is what Ford was telling people, as a maximum.
Seems to work.

I was over filling mine when I first got it, and am lucky I didn't screw it up.
Chris

 

When I had my bike in the back of my truck I got better mileage than I did without......wierd but true, I guess it is due to the fact that it lowers the rear down out of the air a little bit.

Oh and for some reason I can never fill up ANY after it clicks. The first time I ever filled up my truck, I ran it till it cut off, went back to the pump to click a few more times like I do every other car and it ran over the side as soon as it started....so I didn't click it for a good while and the other day I thought, "eh I'll give this a try again", so I tried to click it after it cut off and it ran over the side again. Maybe this is a characteristic of the larger tank??

 

I wonder if it was lowering the rear end, or maybe the bike in the back broke up the drag, spoiler style? Or maybe, with the bike in the back you drove more carefully? I know I do when I am carrying anything valuable.

My first tank would not 'click' fuller. It was only the standard 26 gallon. This is the replacment tank, same size, and it will take as many clicks as you want to put in it. Of course, as Quintin says, that would be a bad thing.
Chris

 

I also have the big tank, and can't "click fuller."

Never thought much about it...rounding up isn't important to me.

I do get 16MPG avg w/ almost pure highway 80MPH speeds. I dropped to 70 avg for a few tanks and I went up to just over 17MPG. Anything less than 70 and you get runned over around here, and 70 means slow lane(and dealing with merging traffic) so I stick with 80MPH and 16MPG.