Hi Peter, I'm new at this and am a little confused by your post. The GVWR on our 19ft Scamp is 3000 pounds. I believe that is the maximum safe weight for pulling the trailer. Are you saying that by adding tires that have a higher rating you can actually go over the GVWR?
The GVWR listed on your trailer's VIN
card is, indeed, the manufacturer's maximum weight
recommendation for the trailer's total weight
(axle weight + tongue/hitch weight when loaded). If you go beyond that weight recommendation and are involved in an accident your insurance company may tell you that you're on your own for paying any damages, regardless of what tires
you have on your trailer.
sticker lists 3500 lbs for the GVWR. I can't (won't) comment on what's safe for any one else's trailer.
I felt the tires
that came with our trailer were not
up to the task, that when I weighed our trailer after loading it the total weight on the axle
exceeded the tire's
manufacturer's specs. I felt it was a matter of prudence and safety to go up a tire size and load range to make sure I wasn't exceeding the tire's safe load specifications.