Crunching sound means you need to replace your regulators, so you literally need to stop using that windows from this point on until you can replace it. There have been instances of where the regulator cable snapped, causing the window to drop inside the door...even break.

As for virbrating, I've taken the door panels off in the front more than once...still can't find where it's hitting. I've removed, threadlocked and tightened every bolt I think I could find, siliconed little areas where I thought it was touching and nothing changed. I've just learned that if the windows are down, to not let them slam closed on their own but instead to close them completely using my hand.

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