I have always changed my oil twice as often as BMW recommends. My service advisor insists it is not necessary and thinks I am nuts (especially since changing the oild on my E46 M3 cost a fortune). Maybe the oil is good enough to last that long, but all I know is that for a relatively small amount of money I have greater peace of mind...

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Current:

E92 M3 - Alpine White / Fox Red

Retired:
2007 650i Barbera Red
2007 750i Jet Black
2006 M5 Carbon Black
2002 X5 4.4i Steel Gray / Black
2002 M3 SMG Carbon Black
1997 BMW 540i Aspen Silver
2000 BMW 528i Jet Black
1997 Range Rover HSE
1994 Porsche 968