Your question may not have a straight forward answer. There is some work for you to do. If the coach came with bias ply tires, the wheels may not be suitable for radial tires. Consider:
1. Weigh (four corners if possible) the coach as it would be for travel (water, food, clothes, etc loaded). If weighing the coach is not possible, determine the gross axle weight rating (GAWR) for both axles.
2. Take the coach to the tire dealer of you choice.
3. Have them determine if the wheels are suitable for radial tires.
4. Let the dealer know the weight each corner is carrying. Or the GAWR of the two axles.
5. Have the dealer recommend the tire that is correct for the wheels and the weight being carried.
Make sure the dealer provides a recommendation that gives the correct spacing between the rear tires. For me, radial tires are the only way to go.
2005 Newmar KSDP 3910 + GMC ENVOY XUV 37K lbs Moving Down The Road
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