Originally Posted by Mark4310
How do I find a true rating then?
IMO, it honestly doesn't matter. You'll never hit it before you run out of payload. It's a mythical figure that is around the assumption that you'll have a 150 pound driver and literally nothing else in the vehicle.
What really matters is the amount of payload capacity which is shown on a sticker on the door pillar in terms of "the maximum weight of occupants and cargo may not exceed X pounds".
That payload number has to include the remainder of the 150 pound driver (unless you're at or under that), any passengers, pets and anything that you carry in/on the tow vehicle. What's left over from that number is what you can carry in tongue weight.
The tongue weight is typically 10%-15% of the camper's total actual
loaded weight. The dry weight is typically low anywhere from 500 pounds or 1,500 or more depending on the size of the unit and your packing habits. The most conservative go with the GVWR of the TT to figure tongue weight as that gives you a worst case scenario. Truth be told, most of the time no one ever hits the maximum weight for the TT. Pick a number in the middle of the two that makes sense for you and your family.
For me, I try not to exceed any of my ratings. Lots of others choose to exceed some by a little, but no one suggests exceeding them by a lot.