There seems to be a lot more respect for the original engineers here than I would expect. How do we know the engineers didn't spec out loose garbage because it would run long enough and was cheaper, or they simply made a bad call?
Is nobody else constantly redesigning crap that someone engineered terribly to begin with?
I bet the pin was made a small OD for an easily assembled slip fit that wears too quickly.
The original design might well be shit. But it's gonna be at least an analyzed shit, and the complaint is "this is a high wear item" rather than "I'm running out of places to stuff the bodies." I don't think anyone here is saying that this couldn't be analyzed and improved. But that's expensive, time consuming and requires a lot more information.
The OP seems to revel in ignorance, and that's dangerous in this application. For example, what does coefficient of friction have to do with any of it? It's fine to make high consequence parts to a print. It's fine to design high consequence parts. But assuming that competence in one qualifies you to do the other, either way, is a whole other can of worms.