Originally Posted by Thomas G.
(...) Contrast this to a trailer that may sit for months, in heat and cold pulling in moisture with the bearing in a static position where there can be a long term interaction between the bearing roller and the bearing cone surfaces. I suspect that trailers that are pulled frequently need less bearing attention for the reasons stated.
I fully agree with your observations:
Corrosion occurs in presence of humidity and absence of grease. Metal to metal contact of different alloys also invites corrosion. Just think of disk brakes
squeeking after being in contact with metallic pads after a couple of days under rainy conditions. Brearings and bearing races need to MOVE in order to be protected.
The very worst conditions are boat trailer bearings that are regularly submerged and that need to be repacked every season end. Otherwise, bearing races are ruined causing bearing to fail. Even an Ez-Lube hub, designed to be submerged requires repacking at season end.