What would cause my barely used green bearing to do this?
What differences that have an effect on bearing life?
I feel you, can't help yourself sometimes.
The biggest reason is how the axle is designed to handle axial(side) loading. With the 8 3/4, the axle side loading is handled through the opposite side bearing. That's why the center button in the 8 3/4 is so important, it translates the force through the center section from the loaded wheel through to the loaded bearing.
Green bearings are really more for axle designs that don't transmit the side loading into/ through the axle bearings (e.g Ford axles). That's why they're ok for drag racing applications, not ok for road racing, and over-discussed for street applications. The force goes into the Ford axle in a totally different way.
If you look at 8 1/4 axles, the axle bearing rides directly on the axle itself, is a straight roller (not a ball bearing or a tapered roller) and carries ZERO side load; without the clip, the axles just slide right out.
The second gen green bearings are a combo tapered roller (iirc) which is better than the first gen, which were a straight ball bearing, which sucks 100% at carrying side loads. Both of which do not transmit the force the way the factory tapered roller bearing does.
So, the design of the axle dictates the type of bearing needed.
