Originally Posted by 328idogg
See pics below.
The Shadowline trim is the black trim around the frame of the door opening on the car body. Note that some models have chrome trim. Apply RejeX/wax to this part.
On the door side, there are 3 areas (shown in the arrows). I just applied Vinylex to the door seal shown with red arrows. That's the part that actually contacts the Shadowline trim and causes the squeaks. You don't have to apply anything to the felt flocking or the larger main rubber door seal.
Hope that helps.
This is a very helpful thread. I started noticing this squeaking / creaking a couple days after picking up a CPO 2009 328 with sport pkg. Issue was just as others have described. I read these posts then applied Vynelex to both the door seals and the underside of the shadowline trim. It worked completely. I'm expecting it may wear off in a few days, but my local auto parts store didn't have the wax described for the trim, and I was reluctant to experiment too much. Anyway, the fact that the Vynelex worked shows the nature of the problem and points to a more durable solution. Thanks. All!