Tom & Laurel:
If I am tire size and load limits are the same or about the same between different brands and manufactures. The label listed for the maximum carrying capacity of the axel. I would suggest that when the coach is loaded to a trip including fuel and water I would get I weighted to determine how much air to put in the tires. Also check the date on the tires if they are over five years old I would think about putting new tires on. If you check the Toyo Tire web site they have a RV Inflation Guide
you can refer to for more information.