Staying with the Ford brand.....
The new 150's are nice. The only down side when I went looking was I couldn't get an 8' bed and a crew cab. If you can live with a 6' bed than it is a nice truck. Tons of creature comforts compared to my Super Duty
I have an 08 350 diesel CC now and pull 13-14 around town at 10k pounds empty. I looked into the 2011 diesel but could not get crap out of mine trade wise so I'll keep it. The other brands of trucks are tempting but the Fords have been good to me for work. Having previously owned 5 GM's I couldn't keep front ends under them for more than a year. The GM's ride better with the car like suspension under them but squat like a little girl when you hang a 9' plow on the front of it. The older Fords didn't do any better with front ends either. Since the change over to a Dodge style suspension in 06 the Ford front ends have been holding up well. The Cummins in a Dodge is nice. However Dodge does not offer a Mega Cab with an 8' bed. They have what they call a crew cab but it is small compared to the Ford and Chevy. I will admit though the Dodge has to be the best riding 1/2 ton I have ever ridden in, car like smooth. For a persoanl truck I'd say the Ford 150 or Dodge half ton. For a little more truck still on a personal level the GM. For all out work a Ford 350 or Dodge 3500 with a diesel.
Mielage...there are way to many determining factors, gearing, 2wd, 4wd, motor choice, region where you live, year of the truck, etc. The trucks prior to the DPF Regen models netted the best mileage (diesels) 07 Dodge, 07 Ford, 0? GM. The Regen system dumps raw fuel into the exhaust to clean the system. The system put in place to keep them clean uses more fuel! The DPF delete kits while not for road use (emission tampering, blah, blah blah) will net better mileage. However if you live in an emissions area this may not fly.
