Daniel,
Three of the failures were sidewall failures (zipper rips) on the rear tires of my 1993 Patriot that I purchased in 2000. The coach had 4 year old high thread Michelins when purchased, and they all happened within the first 2 years of ownership (2 in the same week), while I was still working and only using the coach for vacations and an occasional weekend. Apparently the previous owner had been running the tires underinflated, and since I was new to RVing, I did not understand the permeant damage that is done to a steel cord body RV/truck tire from underinflation/overloading. Since then, I have had one tire failure in the last 18 years, and that was in 2018 when I hit a piece of metal on the freeway in Tacoma WA. that caused a blowout on the RR outer driver.
Gerald