Dropped off the 280QBS at the dealer and right next to it was a 280QBS with 5200# axles on it. When I questioned the service manager, he informed me that they replaced the axles on that one last year. It was back, because it was still wearing the rear tires in an abnormal pattern. I was told that they would make sure that my axles were upgraded and the tires replaced, just like they have done with the previous units they have had to repair.
Just remember when dealing with the RV Dealer, they didn't build it, and they only get paid to fix the problems if the factory approves the repairs. That said, you want to find a Dealer who will stand up for you too.