Originally Posted by
EbbTide
It could have just been a defect in the bearing or maybe a piece of dirt got lodged in the seal at some point. I wouldn't worry too much unless it happens often. But one thing to check is if there is any slop in the driveline or the rear hubs. Vibrations can cause failures.
There is a little bit of side to side movement on the A Arm but all of them do it, seems off road cars have a bit more play in things than my Touring. I also wondered if the hex nut had some flash or other part of the plastic that was protruding and rubbing the bearing face. Is it worth it to check out the JConcepts or Associated aluminium hex nuts?