From the level of neglect that I see up in the rust belt, I wouldn't be surprised by a failure of any combination of those.
I realized that my ball mounts were getting rusty so I bought 2 of these from tractor supply. 2" and 2 5/16". They are probably overkill for the weights I pull. They are also a little longer than normal so If I tow something with a upright jack, I can still drop the tailgate. I think they were $125 each.