Since my 2010 750i used one quart each 2000 miles, I made sure I had a backstock of BMW/Castrol Fully Synthetic 5W-30 oil.

According to the owner's manual and my dealership, the 35d can accept 5W-30, BUT the dealership also told me that they do not use this 5W-30 in the 35d. They use another "special" synthetic oil for the 335d and X5d.

What would this be? I have A LOT of 5W-30, and the M6 and Range Rover cannot use 5W-30.

Thanks!