Two blowouts, over 24 years ago, on the Holiday Rambler, Goodyear 19.5 tires. The first blowout, actually a complete tread separation, was on an outside duel, I was able to limp about 20 miles into town. The tires were 8 years old at the time but they had good tread and I was young and inexperienced. The second blowout was on the way home from the same vacation, just outside of Las Vegas, when the inside duel on the same side blew, taking out some skirting and a few electrical connections. The cause was probably associated with excessive strain from the earlier 20 mile drive. I now replace my tires, even in excellent condition, every 6 years. Yes, very expensive, but I consider it the cost of maintenance.