My trailer (2005 Backtrack) has greaseable wheel hubs, but they're not the "bearing buddy" brand as far as I can tell. These have a rubber dust cover over the center of the hub. When you remove the cover, there's a zerk fitting in the middle and when you pump grease in, the old grease oozes out from the perimeter of the hub. The dust cover normally keeps all the oozing grease contained. When greasing them, should I keep adding new grease until I see new grease oozing out, or just add "some" grease to it? I suppose the obvious answer is to completely flush the old grease out, but I wouldn't think that's necessary every time I check the bearings. In one wheel, the grease that oozes out is milky gray in color, which means water contamination to me. The other wheel oozes only dark black grease. If it's any more of a clue, the rubber dust cover has the word "WEDGE" stamped in it. Couldn't find anything on the web about bearings or hubs with that brand name... Thanks!