Well, I posted a little while back that I had developed a loud rattle between 5-6k rpm that would last only a few seconds. I didn't believe it was the seatbelt, but it was! But it's not what I thought could be the problem.

What I found out is that if I put the buckle in the clip and push it all the way down so that it feels really secure, when I reach 5-6k rpm, I get this really loud rattle. Well, incidentally, I placed the buckle in the clip just enough to clip it in, but did not push it down any further. Guess what.........rattle gone! I couldn't believe it. So I tested it again both ways and sure enough, this was the solution. However, I do get a very fine (almost inaudible) rattle from the buckle in the clip, but this is very livable.

I also had another rattle coming from that same area. The solution for this was my ignition keys! I bought the metal z -emblem keychain and added my car keys to it. Well, when I drive, the emblem hits the keys and creates a slight but audible rattle. The funny thing is that the sound appeared to be coming from the right passenger side. But it wasn't.

I don't recall how I discoverd this one, but I do know that whenever I hear a rattle coming from the passenger side, I grab my keys and sure enough the rattle ceases.

Hopefully someone benefits from this info.

Good luck!