I have a 2008 Aveo to. Bought it new. I have just about the same problem with the howling. It sounds like it is coming from the right & left front fender wells. It only does it when the wind is blowing about 20 to 30 mph and your on the highway doing about 70mph. The faster you go the louder it gets. What is weird is if you crack the window a little the howling stops. You roll the window up and its back. I've taken it to a dealer who said they fixed it by replacing the weather stripping around the fender wells. It didn't fix the problem and when I told them in a phone call survey that it didn't fix it they said bring it back and we'll see if we can. I said I don't think so. They only had it about 2-hours to fix that plus a popping in the windshield and the popping in the front end. They said they replaced the weather stripping in the windshield and fixed the popping in the front end. They didn't fix any of it. So I took it to another Chevrolet dealership and when they put it up on the racks the service mechanic can to the waiting room and asked me if I had sprayed any wd-40 or some kind of other lubricant spray on the front end. I said no but I bet the other dealership did. They had to replace a lot of the front end parts. I still have to take it back to the dealership because of the howling and I still have front end problems with it still. But the howling is the most aggravating thing I have ever heard. It is so loud that you can't even hear the radio and you wish that you had some ear plugs to put in. I think they left something out when they put this car together. If someone has heard of this howling would you please let me know. thanks LB