EXACTLY!

BTW I have a 1500 5.3 and it gets 14-15 around town empty, truck is a stripper bench seat regular cab. I am 99% sure 3.73 rear.

JS, ex's avalanche was a 1500 also.

Right now for towing, I have a (new body style) '07 Tundra double cab TRD offroad 4.7 5speed auto with 4.10's in the 9.5" rearend. Rated for 8100lbs. Unloaded I average between 20-21mpg. Pulling, I average 15-16mpg. I've been dying to order another new one that's exactly the same with darker interior color, the 5.7L/6spd auto/4.30 gears 10.5" rear, and the optional supercharger that bumps horsepower up to 500 ponies. Nothing like a new truck with a 100k mile bumper to bumper warranty with 500hp

Thats funny..the rating on the widow sticker not even close to those mileage #'s ????

Hey know it all.I put a upgrated chip, K&N filter system and dual exhaust system on mine and thats what it get's.

I pulled a 29OL with a Chrysler Aspen (5.7 Hemi) with no problems.

Those trucks had a 8700 lbs. max tow rating. I hope you towed your 6800 lbs. boat and 1900 lbs. trailer without any other passengers in the truck, nor fuel, water, gear, anchor, tools, etc. etc. in the boat.

In August, I sold my 2001 Chevy 2500HD Xcab with 6.0, 4.10 axle ratio truck. Bought it new in 2001 and drove it 160,000 miles. I got 13ish mph around town, 16ish on highway, and 8ish pulling my boat / trailer (current boat/trailer is right at 8100 lbs, total weight including fuel, and all of the other "junk" in the boat). I bought a new 2010 GMC 2500HD 4 door SLT (11 inches longer then the previous truck) with the 6.0, 3.73 axle ratio. Had many sleepless nights tossing and turning about whether to get the 3.73 ratio or order a 2011 with 4.10 ratio. Now having had the new 3.73 ratio truck for 4 months, I can say with certainty I should have bought the 2011 with 4.10 ratio. Here are several reasons why: fuel economy ... most said I would get better mpg with the 3.73 ... well it doesn't! Its more or less the same: 12ish mpg around town (actually 11.8 most of the time, dividing miles by gallons, not the in-dash computer estimator), 16-17 on highway, and 8ish pulling the same boat/trailer. When it shifts from 1st to 2nd or 2nd to 3rd, there is a very noticable bog ... even without the boat/trailer behind it. Very noticable with the boat/trailer behind it. It always seems like it is struggling right after it shifts, loaded or unloaded. 1st gear is so low, and shifts so quick, it really "jerks" the coupler (surge brakes) no matter how gentle you try to pull away from a stop sign or stop light. I'm getting better at soft starts, but the first couple times, I thought I was going to rip the hitch off the truck, even trying my best to be gentle. My 2001 with the 4 speed and 4.10 had none of those characteristics. I will say though, that this new truck's engine is much more resposive, and has noticable power difference once you get the revs up. Not saying that I'm totally dissatisfied with this new truck (I actually like it a lot), but if I could do it over again, all things being equal, I would get the same truck with the 4.10 ratio and not look back ... assuming you are getting the 6.0 gas engine. I think all Duramax's have the 3.73 and no other option. I posted a thread on this forum when I was making my decision to buy and got about 60/40 in favor of the 4.10, if I remember right.
Sorry for the long post, but wanted to give my "back to back" experience, now having had both.

PS. I put a 35 Lightning behind the 2001 a couple of times for a very short distance (5 miles from storage to ramp on flat divided state highway)... would highly recommend NOT doing that. Would never do that again!