They are a pain... I have one on the drivers side that I can't pinpoint. It happens mostly some over bumps, but also at high speeds (70+). I "think" it is on the lower door towards the hinge, but sometimes sounds like it could be coming from the dash. When I mentioned to a mobile ranger who was out for another reason, he said I'd probably have to bring it in and pay for an evaluation. Since the closest service center is 1hr + away and I have no idea how long it would take or fix I've held off at least until I can track it down better.