Jeff; We got our 4200 in Oct. & now are hearing about the tires. It really ticks me off that we now have to spend another $ 2,500.00 - $ 3,000.00 on tires because the Towmax are useless. I have checked with local dealer on the Towmax, and the response was the same from the all - They, (Towmax) make a very good, middle of the line, tire for utility trailers and light weight RV'S. They experience I they will not stand up on weights much over 12,000 lbs. I guess I will have to get the Goodyear G614 tires before something happens. How d you like your new 2015 350? I have a 2011 & looking at the 2015 now.