[winks79]

I'm having the same issue, but I think I have narrowed it down to the caliper pins. What i have done to figure out where the noise was;
- Drive slow over a bump and notice if the sound comes from the front or the rear (mine was the rear)
- Repeat step 1, but drive over the bump on the left side or right side. For example, I drove over a speed bump on the right side and then the left side. The rattle only appeared with the left side going over the bump. From this I distinguished it was the left-rear.
- Next, I applied the brakes as I went over the bump and the sound disappeared. After inspecting I noticed that I can slightly wiggle the brake caliper, which may indicate that the pins need to be replaced.


Hope this helps.

Yep, this is exactly the issue on my daughter's 13' LTZ/RS. I reported it in a thread on here a few years ago. If you have rear discs, this is what I would check first. Not an issue, just annoying. I don't know that replacing the pins will help. I believe it gets worse as the rear pads wear, and allows more play within the caliper itself. Have not replaced the pads to see, as they are still good, but it is not a safety concern. Her car has 91k miles on it now, and this all started at around 20k miles or so. I too noticed that the rattle stopped when brakes were applied, which lead me to the rear calipers, and sure enough that is the rattle. Both sides on hers rattle, and I can wiggle the calipers and make the exact sound.

 

[winks79]

Interesting. The pins are roughly 9$ so I figure I might as well change them to see if it helps, hopefully it does. I'm not too worried about the rattle, just extremely annoying when the windows are down. Sounds like the wheel's going to fall off or something. I will update as soon as I change them.

Hers is not that loud. Just an annoying rattle.