My 2008 535 had a creak in the driver's door weatherstrip in the first six months of ownership. I had tried a few things related to cleaning them, but not too seriously. It was persistent. At the next service I asked the dealer to handle it. They replaced all the door seals. They were very familiar with the problem. There may have been a campaign on my VIN, not sure. Problem never came back.

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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