20+ stock towing must be a lucky man or that lie o meter is way off.

But seriously is that truck stock or not.

I have a Bully Dog on mine. Good power.
About MPGs I am usually at about 14 per gal.
Any of these guys saying 20+ mpg
never get past 1000 RPMs. Or spend ALOT of time on a flat bed trailer and count that as mileage.
But if Fuel milage is what we cared about I dont think we would be in the sport of Hi Perf Boating

At 65/70 I Get 21mpg According To The Computer In The Truck ,When I Towed The Donzi Up To NY It Ranged 14.6 to 15 ,,,At Same Speed ,,Truck Is Bone Stock And No Reason To BS Thats What It Says,,,Next Trip i Will Figure It The Old Way And See

I went from this 06 to this 2012. Both Duramax. Same fuel mileage with both trucks for me, about 14mpg towing 10k lbs or empty.

Maybe my right foot is the problem :D

Thanks for all the advise guys. Test drove the 2012 2500 4 door short box SRW, what an awesome truck! Might order or hold out for the 2013 3500. The spring setup is pretty neat, the helpers only come into play when loaded so as not to sacrifice ride quality. Might as well get a 3500 if you're spending that kind of money on a GMC truck.

back in the day the 2500 had the semi floating 14 bolt rear end and a smaller frame but when the 2500 hd was introduced the rear end was upgraded to the 1 ton full floating 14 bolt and also it was give the same frame as the 3500. So if you found out that the springs are different then that would be the only real difference along with the wheels.

I would think you are correct. The spring system is pretty neat, the helpers are reversed "up" and make contact with two brackets w/ bumpers that are attached to the frame. It only makes contact when loaded (or possibly if the axle travels that far unloaded). Seeing as the option isn't that much more $$$, I would think it's the only real difference. Please , correct/inform me if I'm wrong.

BTW, it's really hard to get any real information out of a salesman. I can find out more about the truck spending 15min on the GMC website, kinda sad......

Yes the 3500 has different springs, wheels/tires, and axles to pump up the tow rating. There is even an air bag factory option nowfor the 3500. The 2500's share a lot with 3500's typically but new changes in 2011has added a LOT to the 3500 that the 2500 doesn't have. The stability of DEW is so great that now that I have gone that route I am not interested in SRW now.

DRW? To haul a 24' boat or something else? That's a lot of truck!

hes talking bigger later on, a DRW definitely overkill for a 24. really anything under 12k lbs its probably overkill