Before spending a lot of money on new rims and tires, check the model of the tires you have, If they are Goodyear Endurance they are American made trailer tires, all other Goodyear are made overseas and are (China Bombs). My tire store manager that sell 10 brands of tires and has a 27 ft AirStream Flying Cloud. told me the Endurance are a very good tire and is what he has on his AS with over 20,000 miles. I was going to change myself but with that recommendation we are staying with are Endurance. We have a 25ft AS flying Cloud with 10,000 miles.
Make sure to check the Air Pressure before each trip we run ours at 75PSI.