Same truck here with a 5.7L. Pulling my 22FB, my mpg increased by one over the 4.6L I had. I have a Keystone Outback 227 on the way, so that will probably drop, but among all of the 1/2 ton trucks out there at this time, I really think the Tundra is the most capable(IMHO). Plenty of HP with a 4:30 rear end, it will pull a pretty hefty load.
2013 F250 XLT
I now have a Keystone Outback, but I try to help when I can.
Bitter Gun Owner