Fuel economy 3.5eco vs 5.0
 

I have had my 2016 for 3 yrs 15k miles. The best I can get is 14 mpg, and that is really babying it. My friend has the same truck just with 5.0. He gets 19 to 21 and drives it normal. Same gear ratio same package I ran the VIn. Any suggestions?

Are your 5k miles/ year entirely city? I get 15-16 city, but get up to 23 highway (17 3.5EB 157" Lariat).

A softer right foot! ��

Seriously though, FOMOCO advertised V8 power, with V6 mileage.

The eco has the power, with a nice flat torque curve, but when you are in those turbos the motor loves fuel.

My insurance agent pulled his down to 7 or 8 mpg pulling his boat.

Maybe your not reaching full operating temperature in such small commutes. I average 30k a year and have owned both a 5.0 and ecoboost 3.5. Got 17.8 mpg on the 5.0 and 19 mpg in the eco. 4x4 cc with 3.55 rear end in each. I get 14 towing a small trailer so not sure. My 3.5 is 2nd gen and 10 speed so I probably should get 1-2 mpg better then you. Interested in if and how you figure out the reason. Good luck.

The only true test would be to switch trucks for a week. It's amazing to me when I drive with someone who says they have a "light" foot. That is a very vague term.

I would love to put so few miles on the truck in a year. With the big fuel tank, what is that, like 3 or 4 tanks of gas a year? I had a 2012 with the 5.0. I got around 14 with lots of city driving and close to 16 on the highway, but I have a heavy foot and haul The Wife and kids. I just got a '19 with the 3.5 ecoboost. I LOVE it. I was getting 17 on the first tank and on this tank with a lot of highway driving and using the cruise control I was getting 19.8. Both trucks were Supercrew with the 3.55 rear, but obviously different transmissions.

FWIW, I used the 2012 with the 5.0 to haul a 6500# travel trailer for about 8,500 miles. Coming home from Florida, I was trying to make up time and was going a bit faster than one probably should when hauling weight. Fuel economy was sub 7... :-(

I have a 2017 XL STX Crew Cab 4x4 3.5 Eco Boost with Max Tow package so of course 3.55 gears and 10 speed Auto the past few tanks of gas I've averaged 19-20.3 mpg since the weather has warmed up 8.5 miles to work one way 25-50 mph.Average over the 17,000 miles I've driven it is showing 19.0 mpg!!

https://cimg7.ibsrv.net/gimg/www.f15...d2a71a823c.jpg

I had a 99 F350, I drove everyday and sold it about 7 months ago. It was a 7.3 and I got 16 mpg in it.

If driven in exactly the same conditions they should be very close to the same fuel mileage. It isn't unusual for the 5.0 to do ever so slightly better. But we're talking 1 mpg or less. Usually less. Driving conditions make a huge difference, I've gotten 4 mpg over some stretches of road and 40 mpg on others. In stop-and-go city driving 12-14 mpg isn't unusual and on the open road doing 70 or less I get 18-19. Limit my speed to 60 mph and I can get 21. Towing 3000 lbs @ 70 mph will be 14-15 mpg. Over the last 50,000 miles I've averaged 17.1. That is a mix of hwy,city, and towing.

This with a '14 steel body 4X4 Supercrew with a cap on it. I have the 5.0 and 3.55 gears as well.

they sure do. torque peaks at 2500 rpm and basically levels off from there
must have been a damn big boat