Some of these full-floating bearings are oiled by the gear lube from the center housing, while others need to be packed or pre-oiled until lube can migrate down the axle tubes. I've seen new bearings fail because they were assembled dry. I generally try to pack rear hub bearings with multi-purpose grease, not wheel bearing lube, on assembly, and let the differential lube migrate down the tubes and dilute the grease during normal running. Preload needs to be a firm tightening to align bearing cones and cups, then enough loosening to allow the lube to work its way into the bearings. The outer nut needs to be TIGHT to keep the inner nut adjustment correct. I like to get the inner nut as tight as I can without really honking down on the nut, then loosening about 1/4 turn or less, until a lock washer tab aligns, then really sock down on the outer nut, and bend the lock tab to secure it. If there's any issue with the integrity of the tabs on the lock washer, replace it!
Jerry
