We put the new Michelin steer tires on the front axle. They made a world of difference in the ride and no more rivering. One tire and rim took one ounce to balance and the other one took zero, none, nada to balance on a load force balancer. We had them replaced near Decatur Indiana at the first stor of now a chain. I can't remember the name.
The tires were one week old when we bought them. Didn't have four more or we would have installed them on rear axle. They were changing tires bigger than thes on all kinds of semis and farm machinery. A couple of the Guys bounced them around and onto the axles and into back of trucks like 13 inch tires.
The GY670s have a lot of uv protection compounded into the tires. Their expected life is ten years. The Michelins expected life is five years.
The Dealer told me he could not reinstall any of these tire over five years of age for on the road use. However i got fifty dollars apiece for them and a semi driver gave him a hundred a piece.
As long as the GY670s pass inspection they will be on the coach another couple years. A rebalance may smooth them out but they still are a harder tire with more hard and soft spots than the Michelins.
The Rivering problem is an ironclad problem not conjecture. Even Michelin jumped in and said it was this and that. GY said it was becaue ther front axle load is too light and causes the rivering especially when coupled with having to steer constantly. They do not like to roll true down the road. Then they said they didn't have any problem and it was Operators fault and won't make good their defective tires.