I'm hearing an odd noise coming from the back of my car. It could be something loose or vibrating on the inside, but the noise is coming from the area around the gas tank. It only happens when I go above 75mph and not a mile sooner. As soon as I pass 74mph, the noise starts. I'm thinking it could be related to the fuel pump since it sounds like it might be an electric motor or a soda can full of ball bearings. At that speed the engine is turning about 3,300 rpm but it doesn't happen at any other speeds under 75 (I can do 50mph in 4th gear at 3,300 rpm and still not hear the same noise).
As soon as my co-worker gets here, I'm going to have him help me find it. I'm going to go empty my car out now.
It sort of sounds like this, but not as bad.
[youtube=425,350]http://www.youtube.com/watch?v=kGHSnQ_aMVY[/youtube]
edit: nevermind, I found it. Some sort of luggage rack or bracket on the floor. I shimmed it with a piece of rubber.