The manual suggest SAE 0W-40, SAE 0W-30, SAE 5W-40,
and SAE 5W-30
My personal preference is Mobil 1 0W30
BTW, listen to what Castrol web site recommends for 2012 328i
"Thank you for inquiring about what oil is best for your vehicle. Based on the information you provided, your vehicle requires a special engine oil that can only be purchased at your local dealer. Please visit your local dealer to ensure that your vehicle is serviced properly."
