You can contact Southwest Wheels in Dallas for all the information you need.
I've built a couple of trailers using the Mor Rydes and I believe the warranty is only five years.
When you decide to replace them and want to do it yourself you can find replacements just about anywhere. They are going to want your backing plate to backing plate and flange centerline measurements. The axles are set at the factory for lift or drop. So you need to have that information too. Then there is the capacity of the axle, common are 3,500 lb, 5,200 lb, 6,000 lb, Andy 7,000 lb. Fifty two's and 6,000's usually come with six lug drums. 6,000 and 7,000 lb axles have eight lug hubs (5,200 and 6,000 can be six or eight lug).
3,500's can come with six lug or all of the five lug patterns. I put the six lug hubs on our Casita when I changed out the axle because it is the same pattern on a lot of four wheel drives. It is a good idea if you have the opportunity to match your tow vehicle wheel pattern. That gives you an extra spare. Plus it looks really kewel.
Duane at Nuera in Dallas is a genius if you are looking for someone to help you with any questions. He's busier than the proverbial cat in the outhouse so have your questions ready. I prefer Nuera over Southwest Wheel just because of Duane.
Hope this helps.
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