u3b3rg33k

If you didn't put the retaining clips in properly (or left them out), the pads will rattle ALL THE TIME except when your foot is on the brake pedal applying pressure- sounds like a can full of rocks with the windows down. Ask me how I know.

seven11

It's the sunroof

The second day i had my car I heard that noise and for no apperent reason i reached for the sunroof and grabbed that metal piece. That was that

star69me

I had the same sound when I had my 04 530i I just ignored it now a yr later I have a 07 550i and every once and a while I hear that sound so I took my hand and pressed on the headliner where the sunroof buttons are and boom the sound when away so it's up there somewhere and they are lightly tapping like 2 hollow pipes. Haven't heard it lately

jfife83

There is a metal plate/deflector that can rattle very loudly. just need to grab it in the center with your hands and bend the middle down a bit.....had the same problem

rice_rocket88

Well. .i think you guys solved it! Rattle came back the other day so I pulled back the sunroof cover and pushed that metal deflector and it was the noise! Glad I know it's the source and how to fix it! Thanks! !

defaz

I first noticed that rattle when I was test driving my car. I figured the previous owner had a couple dinner plates stacked under the seat or something. I ended up sticking a strip of velcro (just the soft side) to the top of the metal deflector and it hasn't made a sound since.