If that is the 5th wheel your set on, then go for it! But I do agree it will be over your limit for your current ride. It is the "end of year" season, and perhaps you can get a good deal on a new 3500? As for the speculation on the weights, total and pin, unfortunately the only way to be sure would be to load everything up as if you were going to spend a long weekend camping, and tow it down to a certified scale and get it weighed. Not sure if your dealer will allow that before purchasing, but that is the only way you will know for sure what you are going to be towing. Good luck!