I have been swamped with questions on oils and running a few days behind. Up to 5 -10 questions a day, over 20+ forums is a little hectic ATM.
Cheek out the guide or call castrol techies for a chat, they are more than happy to get your calls.

For lubricant selection guide check out the link below:
Castrol Australia - NetLube

Call Castrol tech department directly on 1300 557 998

Rob.