2015 F250 super cab, 6.7 diesel w/3.31 locking axle

10-12 towing and 15 when not. But YMMV. :)

Are you planning on towing a fifth wheel or travel trailer? For a travel trailer with a 1,000 pound hitch weight, your F-250 will have plenty of cargo rating for the trailer, 100# WD hitch system, and still have 1,600 pounds left for passengers and other cargo.

The fifth wheel, with a 150 pound hitch, and upwards of 2,000 pound hitch weight, you might run out of cargo capacity before reaching the GVWR. . .

Upgrading to a F-350 now will only cost about $865 more than a F-250, while in a couple of years when you decide to get a fifth wheel, it will be MUCH more expensive.

Fred.

I would agree with Larry. I get around 11 towing, can get high teens when I'm not. It is very dependent on how you drive.

With the same truck (2014) and a slightly smaller trailer, I get 11-12 towing and 16 not.

I have a 2015 F-350 Super Cab short bed 4x4 with 3.31 gears.
Everyday driving I get 13, on a road trip to SoCal and back at 75 I got 18.
I do tow a work trailer about 20% of the time, without it I would probably be at 14.
I asked my dealer about the mileage, he said to bring it in to have the software checked. He said there is an update and the mileage should be 15-16 combined and 20-22 highway empty.
My truck has 4170 payload which I will need most of for our next trailer.

My '12 6.7 PSD 4x4 CC 3.55 gears 20" tires gets unloaded 16.4-17 mpg mixed city and 19 - 20 mpg Hwy.

I have an '11 6.7 F250 Crew Cab 4x4 with 3.31's. Around town it's good for 15-17, and highway at 70-72mph about 22.

Ooops

Is that all these new diesels get on the hwy not towing, high teens? Sheesh! I could get mid 15`s when I had 3.73`s in my 12 years older V-10!

I've been getting 12-13mpg towing on reasonably flatish terrain and around 19-20 unladen. Very happy with the fuel economy of the 6.7 with 3.31's.