I just bought a 48 6400 on ebay. What an adventure. I am repairing the rear brakes and the axle seal surface is damaged. It looks like someone might have welded on it then ground it down. Not pretty. Getting another axle housing is not an option! I tried the local places around Tulsa for a repair sleeve, but no luck. I know someone else has surely had this same problem. What did you do? I might make a repair sleeve on a friend's lathe, but I would much rather by the silly thing. The size is exactly 3 and 3/16 inches (3.187). Old school forever baby!