Flat tire on SW Truck while carrying a TC?

On my way up to an engine show in the UP last summer I went through a bunch of sealcoating, I think they got the material from an old Junk Yard. I picked up a three sheet metal screws in the back duals, didn't notice a thing until I stopped for fuel and smelled warm rubber. I just took the stock furnished jack out jacked up the back and changed the outside dual. The trailer I was pulling was about 3,000 and had a 5,000 pound engine on it. I could have taken some tongue weight off with the trailer jack but it wasn't needed. I suppose the camper goes about 2500 + loaded.