We came in from boating and found one of the bearing covers missing off the boat trailer.  So when we pulled the boat the bearing got wet.  It does not seem likely the cover came off driving from the campground to the ramp since it had been in place for about 5 years through lots of potholes.  My guess is someone lost one on the way to the lake so they borrowed ours.  Hopefully I am wrong.  A quick trip to the auto parts store for a new cover and a repack and we are back in business.  Guess I should rub some mud on the new one!  Those shiny stainless things are too tempting to some folks.