Were you by chance going down the Hiway and stop and when stopped walked around and found that this 1 tires what hotter than blue blazes? I cannot answer your question, but this happened to us 2 years ago enroute to FL. Ended up taking wheel, drum off, cutting brake wires and removing entire brake parts. No further probs. Called Dexter when we got home, sent them pics and they sent me a whole new set of things. Never did find out the cause. Ran it w/o brakes on this 1 tire rest of the year and installed new parts in spring of '19 at it's inspection.