Don't be jealous Tom, my trucks purpose is to be a commuter, yours was built for the heavy lifting.......and lift heavy she does!

 

On my 5.0 motor I have the 3.55 gears. I tow only a few times a year. And total weight is about 3-4,000 lbs. If they would have had the same truck color and options as mine I would have gotten the 3.31. For what I tow that would have been fine. I do a lot of highway driving.

 

Over the last 8000 miles the computer shows 18.8 MPG for my 2012 EB 4x4 SC. Never bothered to hand calculate, but then, I really didn't expect to get an economy cruiser either. I think it is pretty good for a full size truck.

 

Right now with this cold and snowy winter, I'm averaging low 12's (lie-o-meter is low 13's). Summer average hand calculates to low 15's when not towing. I run Shell premium.

 

19.3 daily commute today.....17.2 all miles driven average since I bought a few weeks back

 

Tom I don't think the door trim , teardown would be worth it for a parasitic gain in fuel economy. As an example, my '11 F-150 would get 18-20's regularly, not trying to be frugal. I actually added "Max Tow" mirrors to that truck, and noticed zero difference in mileage with them.

Not too much to be jealous of here, I have not read one post of someone with Max Tow, or 3.73's getting into the 20's or even 18-19's.

I know I care WAY more about my trucks capability, than I do about mpg's, I also love my 3.73 gearing.

 

I guarantee that if I had a max tow truck, I wouldn't be bragging or complaining about MPG's, I'd be showing pics of all the stumps I pulled.

 

I think I may come close - I've got Max Tow, 3.73's, 4x4, crew with short bed and am getting around 16.2-16.5 in mixed driving. That is with the 10-30 degree weather we've been having around here. I know with my car I usually drop 1-3 MPG's in the winter. So I'm hoping in the warmer weather to break 18 on the highway.

Anyway I'm pretty much dead on with the window sticker so I'm happy.

 

What tires and running boards are you running?
I have the same Max tow, 4X4 etc with LT/At tires, factory fixed running boards and getting 2 mpg less, lie-o-meter currently at 14.3.

 

I've got the stock Lariat running boards and it's got Hankook Dynpro tires on it, nothing aggressive. The dash says 16.3-16.5 and I've found the dash to overall close to hand calculations (which are quite error prone).

 

Why are hand calculations error prone? Or is the dash numbers error prone?

 

I have the same boards.
Looks like it the tires.
Are your tires All Terrain (AT) or All Season?
Is the size a P or LT?

I'm really curious about this..

 

I've used an app called Road Trip on my iPhone to calculate MPG over 70k in my SHO. Just got the F150 and on my 2nd tank so not much real data on it yet.

I've found the dash #'s to be quite accurate over time. I think it's because the computer knows exactly how much fuel is going into the engine at all times. It can use the O2 sensor, injector duties, etc. Over the 70k the average from the app and the dash are very close. But the app data has peaks and valleys.

Hand calcs can be accurate but over time. They are this way because we never know what "Full" is as it varies from tank to tank. Each pump's "click" can be different and put a different amount of fuel in the tank. And if you try to "top it off" you can get vastly different amounts for full. I know I can influence the hand calculated MPG just by either letting it click, top it off or anything in between.

But over time the #s will converge and get very close. But we're talking thousands of miles here not a couple fill ups.

That's what I've found with my experience but I'd be interested in others.

 

Without going out to the truck but going by the receipt as to what the dealer put on it when they got it as a trade I've got:
4 Hankook Dynapro 275/65R18 tires. They look an awful lot like these:
http://www.tirerack.com/tires/tires....ynaPro+AS+RH03

 

Thanks, that's an All Season tire.
Mine are Good Year All Terrain tires, more aggresive. A buddy of mine read an article somewhere about A/T tires can cost as much as 1 - 2 mpg vs. A/S tires.
That appears to be the case here.
Other things of course are driving habits, fuel blend etc.

What year is your truck?