Welcome to the group, socalcamper. I would suspect that your tire wear might be the result of:
a) axle/alignment problems
b) worn suspension components - shackles, bushings, etc.
c) unbalanced or out-of-round tire.
If your tire is not balanced, correcting just this problem without having first looked at the other possible causes at the same time, would be a waste of time and money. The tire will become unbalanced again quite soon.
Let us know what you have found the cause to be.
2008 Cougar 5th Wheel 27RKS
2005 2500 GMC Duramax