Originally Posted by jstetson
I received the new Belleville washers from Airstream - thanks to Chris Burch a Service Coordinator at the mother ship. There were actually two bolts with broken washers on two separate axles and I had enough to replaced both of them. These washers are stacked two per bolt on the bolt head side. A good visual inspection is all you really need to see which ones are damaged. As for my opinion on this - Belleville washers are essentially small springs used in places were you'd want a consistent clamping load to be applied. In the case of the axle mounts, I noticed that the bolts actually go through two slots positioned at 90 degrees instead of a round through hole. So, it makes good design sense to use the Belleville washers in this case as opposed to relying on just the tension of a bolted joint with flat washers. I don't think the issue is one of design, the method of failure is typical of brittle steel caused by poor heat treat on the washers, or even possibly stress corrosion cracking. Regardless of why, what is important is that you keep an eye on these items and replace them when they fail.
Mine looked very similar to yours. I ended up replacing all of them and painted them before install. As mentioned earlier, stress corrosion cracking looked to be the cause in my case. 5 of my 8 were broken.