I have a skid steer that weighs about 6000 pounds and a backhoe attachment that weighs about 1500 pounds, that is the bulk of my load. I bought a used trailer and do not know the GVWR. The plate on the axles is stamped dexter p21 6000 pounds. They have six lugs and brakes on both axles. It is 16ft with a 2 foot dove tail. I would have assumed it was a 12000 pound trailer. The problem is that the other day I was under it adjusting the brakes and noticed that the axles have been bottoming out on the frame. The frame is only slightly dented for know, but it may get worse in a bad way. So I was wonder why it is bottoming out and what can I do to stop this from happening anymore? Thanks for the help swim.