I have a new 2011 Duramax 3500 swb/srw/4x4. I have had it about 5 months and really haven't put any miles on it yet. (I use the wife's car when we aren't traveling.) That will change in May when I start pulling a 16K 5th wheel. My long gone 2005 6.0 powerstroke was getting about 15/16 solo and 9/10 pulling under normal conditions and I was wondering how the Chevy would do. My question to you is will the Chevy do better (smileage), worse (frownage) or about the same (sameage) as the ford?

smileage for sure

Just need to get it out there and drive. Most do pretty good out the factory. Some don't do so great. No reason why.

Brian

Each truck is different. Depends how you drive.

better (smileage), Chipped/tuned better (ssmileage), :D

Should be about the same at first till it's broke in. Just drove my dad's on a 120 mile round trip and it got 19+ empty. It has 7,000 miles on it now and just recently started getting a bit better mileage, before it was getting 16-17