- a helical LSD doesn't "use" any oil
- Honda MTF, Redline MTL, or whatever normal Honda tranny fluid you use is OK (no special additives needed)
- always check OBX LSDs prior to installation for the proper assembly (in many cases they are assembled wrong -- see links below)
- get the factory shop manual to see the procedure.
OBX diff assy/disassy info:
http://www.marcuccimotorsports.com/j...isassembly.pdf
...and washer replacement info:
http://www.marcuccimotorsports.com/j...eplacement.pdf
credit given in the documents as to the source (ripped from honda-tech and the web)