I realize that BMW only sells it as OE and in 20 liter size for MSRP $616.48 (which is $30.82 per liter!) (not sure why you are being told 60 liter?). Still you could buy a liter from another source (see below) for much less, of either the OEM Esso fluid, the OEM Pentosin fluid, or the aftermarket Febi fluid and have your answer pretty quick.
OE from BMW: (20 liter size - $638.25)
Pelican Parts - Product Information: 83-22-9-407-807-BOE
OEM from Esso: (1 liter size - $16.95)
Go to
BMW Parts and BMW Accessories | Bavarian Autosport and do a search for it. Their system won't let me post the link. (see attached photo below)
OEM from Pentosin: (1 liter size - $16.75)
Pelican Parts - Product Information: 83-22-9-407-807-M210
Aftermarket from Febi: (1 liter size - $14.25)
Pelican Parts - Product Information: 83-22-9-407-807-M36