I have a 1999 Audi A4 with about 111k miles on it. About 3 weeks ago the rear end of the car started to get very noisy. Anyone who sits in the backseat says it sounds like they are riding in an airplane. It seriously sounds like a wind tunnel back there, and I am wondering what the problem might be. I just had two new back tires put on, and that didnt help at all. If anyone has any ideas, I would appreciate the input.

 

correct me if im wrong but the problem could be that your bumber is coming loose and is causing wind resistance

 

Ok hows about we go back to basics.
What sort of noise? external or internal?
Does it get worse as you go faster?
Is it a rattle, rumble or wind being forced through a small hole?
Any affect on handling of car? Shuddering? Pulling to one side?

 

It sounds like it is coming from underneath the left rear side of the car. It is definitely almost a rumbling noise that gets louder, the faster I drive the car. It doesnt effect the handling whatsoever.

 

Are we talking Quattro? It's possible a wheel bearing is shot to hell, or you may have something stuck in the brake caliper? Possibly a directional tyre pointing in the wrong direction?

 

Ya, it is definitely a Quattro.

 

They are the only things I can thing of unless you run over some wire that has wrapped around something. Really need to hear it. Sorry.

 

Thanks for your input dude!

 

definitely sounds like a wheel bearing

 

Either your read differential or if it is coming from one side, likely a wheel bearing.

The other distant possibility is a seized brake caliper.