If it is the bearing I think you mean then this is a 3" long oil lite type bearing with the pivot bolt running through it from the top surface of the wing right through with a nut on the lower surface of the wing. It isn't a sealed 'ball/roller' bearing affair.
The only way it can be lubricated is by oiling from the top and if you are lucky from inside the wing at the top of the bellcrank in which the bearing sits. Not exactly an efficient way of lubeing to say the least. This pivot bolt is rarely if ever removed.
The bolt head sits in a nice detent on the top of the wing which is just asking to act as a water trap which will slowly wash any oil out over a period of time and cause everything to corrode if the aeroplane sits outside.
Strange how it suddenly seized though.