First, welcome to the Forum.
It sounds like you are looking at a new FW. WHY?? Unlike cars, most RV come with lots of little and sometimes big things that need fixed - under warranty by the dealer - but still requires returning the FW to the dealer and waiting for repairs to be made, hoping they fix more than they break! A gently used camper will have all of these initial issues fixed and will save a lot of depreciation.
As RVRAC noted, the RAM 2500 is a great truck, but is somewhat limited to how much FW it can tow. There is a yellow label on the driver door latch pillar that will state the max weight of all passengers and cargo shall not exceed XXXX. This means exactly what it says. Add together the weight of all passengers, pets, tools, firewood, etc. to be carried in the truck. Add 200# for the hitch. Add 20% of the FW GVWR as pin weight. This total must not exceed the cargo carrying capacity as displayed on the yellow label.
DO NOT use the dry wt which salesmen love! Nobody goes camping in an empty camper. DO NOT use the payload the truck salesman uses. It is not for your truck! The yellow label is specific to your truck.
http://www.rvforum.net/SMF_forum/index.php/topic,90933.0.html