FWIW,
The BMW TIS has historically said you SHOULD coat the wheel bolts in a thin layer of engine oil. Both the threads
and taper. That's the case for cars as new as the E46 and E60 at least. Haven't seen the E90 or F30 though.
Quote from the TIS.
Quote:
Do not apply oil to new wheel bolts.
In the case of used wheel bolts, apply an extremely thin coating of engine oil to the threads and tapers before reinstalling them.
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http://tis.spaghetticoder.org/s/view.pl?2/06/76
Brand new bolts presumably have a lubricant coating on the from the factory.
I dip the threaded portion into oil and then lay them on a paper towel for a few minutes. That wicks away most of the oil and leave a thin coating. I also dab a single drop of oil on the wheel's bolt hole taper.