Sweet. I just got another center diff and am going to try 50k oil in it. I'm using hyper st spider center diffs. they have 52t gears on them. They are quieter than the 62t (not sure why, still a steel gear) and give more clearence.
http://cgi.ebay.com/OFNA-Ho-Bao-Hype...3A1%7C294%3A50