Make sure that you use only tires rated for MH service. Also weigh your rig loaded as you would travel, and consult a reliable tire mfgs guide as to tire size and inflation. Michelin publishes a great guide that you should be able to get from a dealer or on line.
I suggest that you shop either Michelin or Good Year and look to the tires that they each sell for motorhome service, specifically. While they won't be the cheapest tires, they will serve better and last longer. Both of these companies have developed tire compounds that were designed for motorhome use where the tire sits still more than it is driven. This should make the tires last much longer as current tires should be replaced when they are between 5 & 7 years old. I have a set of the new Good Year, G670s and they are great tires, but not cheap. Six of them cost me $1500 in a 19.5 size.