Ever tested it? Just wondering if the micron rating is different. I have been involved in testing of filters from OEM sources (not BMW) and the same apparent filters direct from filter manufacturers, with the same part numbers, that have different filter media. We tested them with portable particle counter testers (Parker CM20 as I recall) plumbed to the equipment to prove it out. Sometimes manufacturers use the same part number but a different internal tracking number in the manufacturing process.

In our case, we solved a wear problem by determining that a specific oil filter was flowing higher micron particles than the spec allowed, despite the labelling on the filter. Changing the filter supplier saved hundreds of thousands of dollars. Customer went back to OEM filters.

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2007 X3 3.0si, 6 MT, Premium, White

Retired:
2008 535i, 6 MT, M Sport, Premium, Space Grey
2003 X5 3.0 Steptronic, Premium, Titanium Silver
2002 325xi 5 MT, Steel Grey
2004 Z4 3.0 Premium, Sport, SMG, Maldives Blue