Does anyone pull with close to 24k combined with their 2008 3500 Duramax. I need to make a move before next year and am thinking about going to HDT for the weight but really hate to leave my 3500. I am concerned as to whether the new Duramax can handle the load as my 02 LB7 3500 has to use the edge juice in level 2/3 to get the job done. Also, if you have an 08 pulling heavy, what kind of fuel mileage do you get loaded and unloaded?

Vette Racer,
I see it has been a while since you asked, but I'll answer anyway.
I have an '08 K3500 DRW Xtended Cab. It only has approx 4500 miles on it, but here goes: Ny 5th wheel weights 14000 loaded and I am getting 10.5-11.5 mpg towing depending on speed, AC etc. I traded an '06 K2500 SB Xtended cab that got 14.5mpg towing 11000 lbs and 20mpg solo. I traded due to pin weight of new unit and wanted to be safe. I certainly hope the mileage gets better, but it tows fine.
Ed

I pull a 38' 5th wheel with an '06 GMC Dually (same driveline as 2008) that weighs combined 24,935# and have no problems whatsoever. Trailer is a tripple axle with hydraulic disc brakes, truck is bone stock.

I get into some mean grades here in Western NC, some as steep as 14% but most are around 7 - 9%.

Fuel mileage varies from 9 to 11 mpg depending on terrain, wind, speed, etc.

The '06 and '08 GM trucks don't have the same duramax. The '07-'08 have the new restrictions. I don't know the differences other than the exhaust has that particulate filter that self cleans every once in a while (that's what they told me anyway). I wish I had bought a dually in '06 instead of the 3/4 ton. Both of my trucks were stock also as I'm scepticle of the "tuners".
Ed
Ed

I had a 06 2500 and now have an 08 3500 DRW.

My 06 got about three MPG better, but was over wieght limit. (Never trust a sales person)

The new truck/5r just come in at the limit for wieght. I understand the difference in mileage is caused by the partical filter high pressure differential (plugging) which then causes the computer to inject diesel while the exhaust valves are open. A little raw diesel to burn the particles out of the filter. This happens to me about once per tank of fuel. I'm not thinking the mileage will get much better.

I was told today that all brands of trucks are doing the same thing.

Did I mention don't trust a salesman.