Has anyone else experienced this, because my 2000 V10 did the same thing? On cold mornings, those when the temp is freezing or below, it sounds as though the windshield seal has frozen. When I hit any sort of bump the whole thing sounds loose, almost like it's going to pop out. I talked to the local auto body guy and he had never heard of this problem before. Like I said, my '00 did it, so the problem can't be unique to this particular truck. Any help, advice or info is welcomed, even if I can't solve the problem, at least I'll know what is causing it.