Repacking the Bearing through a Reputable Boat Trailer Parts Shop

"The removal of the cotter pin enables the user to safely dislodge the wheel hub from the main axle and set it aside. Tap on the unit lightly with the inner side facing down to gradually remove the inner bearing and the grease seal, which may have to be replaced. When the bearings have been removed, set the hub aside and clean the bearings immediately. Inspect the bearing rug for pits or scars; finding either or both on the bearings will warrant fast replacement. A company like Champion Trailers will have a hefty supply of boat trailer bearings in stock, but you must ask if their bearings are of the same size as yours."
http://blog.championtrailers.com/repacking-bearing-reputable-boat-trailer-parts-shop/