4500 thats when i like to turn the radio off and just listen and enjoy

 

I have a 2011 with the 6.2. I'm running the same size tires you are, stock exhaust and air filter. I have an SCT Tuner with custom tuning by Mike Butler over at 5 Star Tuning. I have done little towing with it since I bought it about 8 months ago. Running the 87 octane economy tune, combination 50/50 around town and highway, the truck averages about 12 mpg. Did a little better with 265's on it, but not much. It got 13 on a good day before I put the 285's on it. Drove it to the beach and back, which is about 150 miles round trip, and it got around 15, but that was with the 265's. I traded in my '08 F150 on this truck, and traded in about 3mpg as well. It's a big, heavy truck though. I'd say 9-11 towing is pretty good.