I have a 2005 MR. Took out the entire rear interior of the car to clean and took it for a drive. When it gets to atound 2500 RPM I hear a rattle coming from the rear of the car. If the RPM is lower or higher than 2400-2700 the rattle goes away. Doesn’t affect how the car drives at all, sounds like a heat shield or something vibrating fast. I was under the car not too long ago and my driveshaft has a lot of play where it bolts together. I feel like there should be something to hold it still like a hanger or something but idk. Sounds like the sound is coming from the trunk area though, any ideas?

 

On my 2005 SSR the trunk lid torsion spring bars vibrate against the rear shelf at exactly 2500 Rpm (83 Hz). I insulated them with some closed cell foam rubber - problem solved!

 

I’ll look into it, thank you