got the kaaz in last week and looking to get rid of my old J30 if anyone's interested. this diff was in my car when i got it (~2.5 yrs ago) and seemed to work decent, although i did notice only one wheel of smoke at a couple of drift events last year which led me to believe it may have been on it's way out. i changed the fluid in it before drift fury 4 last year and it seemed to be functioning ok after that though. since it's not in 100% perfect condition, i'm only wanting like $150 or so for it, so if anyone's interested let me know (bound to be better than a stock open diff).