What would cause my barely used green bearing to do this?

See post 20 & 21. People have been having problems with these bearings for a long time. Then there are people who say they have never had a problem.
Im one that never has had a problem with them because I run the proper stock tapered bearings like mopar designed them with.
Werent the green bearings a ford thing? Do you really want (F word) parts on your mopar?