I don't like those radial roller thrust bearings in any application - they don't actually roll. .
And you know why don't you......The outside of the rollers want to turn faster than the inside (inner distance versus outer distance travelled on a revolution of the bearing, think of a record on a turntable) , which causes flats on the rollers.
Hence they end up just sliding = then disintergrate



.. thanks for the info, I'll print it off and save it just incase it turns out to be the cam follower.