you can run it through www.realoem.com and see what seals and stuff can be replaced ahead of time and have them on hand. Theres not too many people running the self leveling on here but I have see posts about leakage.
http://www.bimmernut.com/wwwboard/e34/si.html
Bookmark that link...it is your friend! Heres what it turned up for me:
http://www.google.com/search?q=self+...ww.bimmer.info
95 E34 530I V2.37
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Those who make peaceful revolution impossible will make violent revolution inevitable.
John F. Kennedy