What gear ratio do you have?

 

I have the 3.55 locking diff. I also stuck with the 18" wheels, did not really want the 20" wheels. When I kept my speed down, because truck only had 250 miles on it, while towing the boat I got 13.5, but I was being very careful to keep my foot out of it. It also seems if I kept it at 70 mph, I can get 12 - 12.5 mpg pretty easy, maybe even 13.

 

We just got back from a trip in my friends EB pulling his 6500lb trailer we got 7.9 mpg on the way out loaded and 8.4 on the way back downhill. The truck pulls like a dream but the mileage is absolutely brutal. This was at 65-70 mph on the freeway and 35-40 on the windy hills. Hills and headwind will really affect the mileage.

The EB is a nice truck but If I wanted to tow more frequently I seriously be looking at a Super Duty.

 

Have you towed that same trailer in similar conditions with a different vehicle? What sort of mileage were you hoping for when towing at highway speed in the wind?

 

Towing mileage is an oxymoron.

 

I have an 2010 F-150 4.6/3V and I get about the same with no where near the power output... 😜

 

I have a 2013 with the 3.5 Eco and tow a 34 foot travel trailer that's over 11 feet high and get between 8-9 mpg.

 

I just upgraded from a F250 to the F150.
The F250 was a super cab with a 5.4L 3:76 rear end.
the fuel mileage towing my 28 foot TT was 7 mpg, my 19 foot boat was 14 mpg, Truck empty highway was 15 mpg and back and forth to work was 9 mpg.
My new F150 Crew Cab has the 3.5Eco boost, 3:55 rear end, large fuel tank and the big towing mirrors which do drag in the air.
Towing my Travel Trailer, I get a disappointing 8-8.5 mpg, but I can finally maintain my speed going up hills and mountains, Yea! It beats the old truck right there. Highway I just got 19 mpg from Ohio to Virginia to North Carolina and back through West Virginia including my time driving in sand on the beach by Corolla NC with two people and camping gear. My mileage to work and back is 18 mpg compared to my old 9 mpg. I haven't done the boat yet. It's a massive improvement in fuel mileage and ride quality.

 

Nice, I am sure you will love it! In the long run, the fuel savings will be very worth it, and you will still have comfort in ride etc.....

 

Just a little towing info on mileage! With my 2009 F150 with 5.4 engine and 18 foot flatbed trailer I hauled a Chevy S 10 pickup from Indianapolis to Louisville running 75 MPH and got 12 MPG from it. Same truck similar road pulling a 12foot single axel flat bed with 600 LB ATV on it and got 9 MPG at 75 MPH. I haven't towed much with my 2015 F150 with 2.7 but what I have done I'm getting about 17 with 18 foot trailer and 3 ATV's running 60 MPH

 

I'm missing something. Surely you have the MPG's swapped - towing the ~3500 lb S10 on an 18' double-axle trailer couldn't have gotten 12 MPG when towing a 600 lb ATV on a 12' single-axle trailer got 9 MPG at the same speed on a similar road with the same truck. So, what did I miss?

 

Didn't miss anything! That's how it was!

 

I don't pay exact attention to my towing mileage, if I did I probably wouldn't go anywhere. Towing my boat (dry weight 4,200lbs) with my 3.5 EB I get slightly better mileage than I do towing with my 6.2L Super Duty. Towing my car hauler it is reversed, the 6.2L does a littler better.
The Super Duty is over kill for me, but it was considerably cheaper to purchase than the F150 so I thought I would have some fun with it.