boqibama - your car doesn't use bmw's transfer case oil, that is for x-drive systems only.

dchen8 - good info, though keep in mind that numerous manufacturers have products that will 'meet the spec' (however ambiguous that statement really it). Personally I wouldn't chance it with something that 'should work' rather than using something that 'does work'. Especially when it involves something that gets changed so infrequently and the price difference will come to +/- $50 on an $80,000 car.