13.8mpg empty 75-80mph Highway 80%, City 20% combined

 

Mine came with the 4.10's which actually help in city and in town driving. I'm in 6th at 38 mph roughly so I'm getting 14-15 in town and 16-17 on the hwy provided I keep speeds in the 65 to 70 mph range. 3.55's should do better on the hwy keeping the cruising rpm's in the 1700 to 1800 range. Best is when I nudged right over the 19 mpg mark but speeds were in the 50-55 mph range on some of out narrow 2 lane hwys. Land here is flat as a pancake so I'm not pulling up hills or mountains...just tall bridges over the Mississippi River!!

 

Had mine about 2 months now. Mostly short distances and it is 4.10 rear. Getting 14.5-15 mpg. On long drives about 17 mpg. On a previous truck, a 2009 best it ever got was barely 13. That was found downhill, wind at my back, etc. This truck is much better. I figure the 2020 - 2024 trucks will finally have diesel and pollution control finally figured out

 

 

I'm running 4.10's and when running 65-70, my dash says low 13's. That's it.

 

I agree. 55-60 mileage is pretty good but above 65 it drops 2-3 mpg

 

I have a 17 F-350 CC DRW with the 3.55. Little History, I had a 11 srw and got 15-17mpg. I bought a 15 and it went to 14-15mpg (they said it was worse but i didn't believe them). Then i went to a 17 SRW and was getting 15-16mpg. I towed my 15k lb 5er to Florida and back and got 9 mpg averaging 70mph (slow down to 65 and it will jump). I had some sway with 15mph winds but the thing rocked the grades thru Tennessee. I would hit 2-3% grades and didn't even down shift most of the time, then 4-6% and it would usually go to 4th and climb it and not think twice. I decided since it did so awesome that the DRW didn't need the 4.10 since it was my daily. It took some searching because everyone must want eh 4.10. They had 1 platinum in White platinum in a 1000 miles radius. I am getting 14.5-15.5mpg. This a fair range of around town to interstate some. I don't drive like a gma, but also not like i stole it. Cant wait to get my 5er on it.

 

2017 F350 Dually 3.55 6.7L 4WD CC LB Lariat

 

 

 

4.10 6.7 DRW CCLB. Mostly highway in mid-Atlantic. Lifetime is 14.6 on trip 2
Calculated 14.65 over 5300 miles.
Averages are increasing since I started adding PM22 Cetane booster two tanks ago.

 

 

 

Had 4.10s in the 2006 and went with 3.55s when I ordered the '17. I get 14 - 16 mpg usually. That is hand calculated, not the BS the computer tells you. I don't drive on the highway that often, back roads and 45 - 55 mph two lane roads. I drive near the speed limit, no sense wasting fuel or chance of getting a ticket to save 2 minutes. If people want to go faster, pass me, I'm bigger than them anyway.