Junior. I'm seeing about 14 and sometimes 15 in the 2010 CC F250 4x4 short bed
The '08 with flatbed is seeing max 12-13 but it's a DRW, CC 4x4. Towing sucks. 7.4-7.9 mpg with 12-14k weight.
I have to admit. Compared to my 2005, which I was very used to, the '08 and '10 are a joy to drive and work from. I have the captains chairs and the center console is so much easier to write on or access than the earlier models.
The ride is smooth and I have plenty of power with NO mods yet. The only complaint is fuel economy towing but I don't think there is much of a fix with the weight and aerodynamics of towing.
Make sure you get a winch. The winch bumpers look very cool on these trucks and I've already paid for my winch in what would have been recovery charges. I didn't post about it but nearly sank my Bobcat in a lake earlier in the week when it "slid" down a concrete dam that was covered in a slimy algae. So much went through my mind but I didn't panic and dropped the grapple into the concrete effectively anchoring me while I ran uphill to get my truck. Winch got me to where I could put a chain on it and the power of the 6.4 in 4 low pulled a 10k Bobcat up enough to get traction. I wish I had bought a 12k winch but only had enough money for an 8k. Going to upgrade soon!
"Life is tough, but it's tougher if you're stupid."