stacker12

I have a Screw 157" 3.5 ecoboost/3.31 gears with 2500 miles on it. So far, my towing mpg has been horrible. Towing a 17ft jon boat (approx. weight with trailer 1500lbs) at an average speed of 70 mph I got 13.7mpg. Towing a 6x12 enclosed trailer with little cargo at 70 mpg I got 8-9mpg over a 3 hour trip. These numbers are worse than my 2008 Tundra with the 5.7L. Can I expect these numbers to get better after break-in? I often am towing a boat (2000lb or less) when driving on the highway so I am worried I made the wrong engine choice.


Thanks for the feedback.

AbitaPro

Is your truck stock? If no, did you install larger tires and a level or lift? If yes, have you had your speedometer recalibrated? If no, do so.

All said, the mpg sounds in the range of normal, some may get more, some less, as their are lots of variables which may affect mpg. One must realize it is a gasoline engine with a turbo, if you have your foot, or the load, whatever it may be, is in the turbo, mileage will fall. Now if you run 55MPH, variables change and mpg will increase.

Best bet, don't look at mpg and enjoy your new truck.

Shabs

sounds like you may of made a wrong gear choice not engine choice.... you may get 1-2 mpg better when broke in although i wouldn't expect it. 14mpg towing anything at 70mpg isn't that bad in my books its more the extra drag even though its only 1500lbs. Ive gotten 14mpg average just on a strong headwind day not towing at all, ecoboost is for people who love the 420ft/lbs or tow a lot of weight not mpg although some members seem to get decent milage somehow.

stacker12

The truck is completely stock on 20" sport wheels. Would the 5.0 get better mileage towing light loads? My dads 09 Sierra with the 5.3 definitely gets better mpg towing these same loads. Also, in my situation, would gearing really make much of a difference in mpg? Since I never tow really heavy loads I figured the 3.31 would give me the best mpg on the highway, even with light towing.

BStrummin

Those are normal numbers based on my two ecoboosts and towing a 18 ski boat and a 30 TT (not at the same time ). And my brothers Tundra gets almost exactly the same - we have almost identical TTs and we both get 8-9mpg pulling them into the mountains. My 36 gallon tank however makes the trip way better. What kind of mileage does that Chevy get? Also 70mph is kinda quick to be towing. I'm just used to towing at 55 because it's the law here and you will get a ticket, but the tradeoff is a smoother tow and I've always assumed much better mpg.

HCFX2013

What I observed:


Towing my 7x16 enclosed ATV trailer at 70mph: 11.2 mpg through the hills
Towing my 7x16 enclosed ATV trailer at 60-65mph: 14.7mpg through the same hills.


Speed is hugely important especially when pulling a box through the air. I bet you'll see a huge improvement by dropping your speed back even a few mph.

stacker12

I understand that cargo trailers get crappy mpg, especially with headwinds. My main concern is pulling light boats as I was expecting better mpg than I am getting. With an 09 GM I've gotten around 15 mpg with these same boats at similar speeds. The GM pulls the cargo trailer at 10-11 mpg.


There is no special speed limit for towing here. When doing 70mph this is on 4 lane highways or interstates.


How many miles until these engines are considered broken in?

Viper556

That's about what I get as well. Kind of disappointing, but I don't tow much anymore. My 6.7L diesel does much better.

Moore08

I would consider that mileage normal, I wouldn't think you would see much more mpg with the 3.55 gears and I doubt the 5.0 would do anybetter, maybe slightly .. The one thing I have learned about the ecoboost engines since I bought one in 2011 and my 2015 has one is that they have a huge fuel mileage range depending on how hard you run them .. Pay attention to your driving characteristics and put that low end torque to work instead of revving them out .. I was able to gain a couple mpg's just by learning what works and what doesn't for these engines

RceRdFX4

My 5.0 seems to do a little better on mileage towing but not much, the thing to remember is even if your rpm is low you are forcing air in so it will use more fuel, gotta have it to make the power no matter the displacement.