Hello DBECHEN We are now proud owners of our first Fifth wheel Big country 3450ts and just went through the same cenario as yourself we have a 2008 2500hd diesel and was told by another dealer said should have no problems so I called gm manufacturer directly gave them vin # told the lady exactly our intentions and a day later gave me the specs ours is only good for 13600 so we are over weight with my wife under 3yrs to retirement I now have about 8months to look for a 3500 lol as we don't take possesion till spring hope this helps