elliot,

I may be wrong, but I believe the GCWR for that setup is #18,500. You'll need to weigh your rig with a full tank of gas, tools, generator, people, and whatever else you plan on carrying in it. Then subtract this from 18,500 and that will tell you what is left for the max weight for a 5ver. But you also must watch the pin weight of your 5ver. Your pin weight and the weight of your rig can not exceed your GVWR, which you said is #11,500. Word of caution, ignore the unloaded vehicle weights on the trailer, use the GVWR. Once the 5ver is loaded, food, water, clothes, camping gear, etc., you will be close to the GVWR.

An easy way to figure out what your loaded pin weight is this...you can figure 20% of your 5ver's weight will be pinweight. So say the weight of your 5ver is #10,000, you can figure your pin weight will be #2,000.

Hope this helps.

Rich