Oil colour is not an indication of quality or cleanliness. New oil is generally gold coloured, but after that it doesn't mean a thing.

Diesels are a good example: the soot will make the oil black in 5 minutes, and that is normal.

The exception is if the oil is milky, indicating likely water in the oil.

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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