I haven't done the tape but there is an exact process did you find the BMW directions or just "wing it"?

My roof rack crossbar goes right over my Glass. I cut a piece of wood just the right thickness to push down on the glass and pulled the fuse. Zero rattle.

I just realized what I thought was crossbar was just part of a roof per such in the background of your photo.

Somebody to cure a leaking roof used some quality tape to seal it, that might also work for the Rattle.

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2011 E70 • N55 (me)
2012 E70 • N63 (wife)