6 years on toyo m144’s 45000 miles . Minimum tread wear and sidewalls look like new. Had cracking Michelin tires prior. Michelin make rv specific tires by using less tread depth ( you’ll never use all of a 150000 plus mile truck tire ) and softer sidewalks. I didn’t like them and they were cracking at 5 years old .. put on by the prior owner. the toyo tires ride just as well. I was told the toyo was designed as a bus tire to take abuse that RVers like hitting and rubbing curbing. Preparing over the next couple years replacing with the same even thought they look perfect, just for peace of mind .