You have sticky summer tires and painted extended flares. Those sticky tires pick up more rocks on the road than normal tires and flings them to the fender. I have an M3 and have this issue as well. The only way BMW could avoid this issue is by having non-painted fender flares (plastic). I say just enjoy your car.

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| 2009 E90 M3 | JZB | Black Leather, Carbon Leather | M-DCT | 19" OEM Wheels | Tech, Premium & Cold Packages | PDC | Alarm | Premium Sound | iPod Adapter |
| 2011 X5 35i Sports Activity | Sapphire Black, Black Leather, Dark Bamboo | Convenience, Tech & Cold Packages | HUD | Comfort Access | Premium Sound |