I have 2 examples... Both 2nd gen' B'cudas. several years ago, I found a upper bearing rusted away so bad that most of the lil balls had fell out. More recently, while working on a automatic shifter column... I hadn't noticed a problem with the upper bearing while driving the car but spin the wheel on the workbench and that bearing roared. It was quite crusty also. Danged if I know why. One was in a convertible which could explain it but other was a notchback. Rain blowing in open window?