Here's my improper hauling story...
A few weeks back I went to pick up some hay with my new (to me) gooseneck flatbed trailer. The guy I was buying the hay from had a neighboor bring his tractor from down the street to load the 800 lb. bales. Once I was loaded the tractor took off one way, and took of the other. A mile down the road I saw smoke coming from the trailer tires. I quickly pulled over and found that the weight of the hay had dropped the deck of the trailer down to where the outside frame was just barely rubbing on the outside edge of the tire tread. I didn't have any way to lighten the load. The tractor that loaded me was long gone by then, and the trailer that I would have needed to bring my tractor back was loaded with hay. I figured at this point that the tires on the trailer were no good to me if they didn't fit the trailer. My only concern was that the tires get me home where I could unload and that I not light anything on fire.
I drove the 8 miles back home by going slowly until I saw smoke, and then stopping for 20 to 30 seconds to let the tires cool. It took about an hour to drive the 8 miles home. By the last 2 or 3 miles I had rubbed enough rubber off the sides of the tire tread that I could go almost 25 MPH.