I have a 2008, Impala, and at highway speeds and the window wide open, get a wind whine. Now, the problem is, I just had the windshield replaced and wondering if that has anything to do with it.
thats interesting- I dont think the 06-08 have any rubber around the windows like other cars... id look around to see of anything is sticking out. check the wipers too..... also- is it a whine around the outside of the glass or internal? One thing you can try is if you open the drivers window- and you get the noise.... try opening the REAR PASSENGER window just a little bit (little crack)..... see if that changes anything.