I'm having some problems with my 01 Grand Prix. The front end is roaring when I get up to about 20mph it will do it from here on out to about 70, then the noises of the highway and such drown it out. It's not really a vibration because you can't feel it in the steering wheel or anything. The best way to put it is...it sounds like I'm driving down the road in a jacked up truck with super swampers; that annoying little hummmmmmmm!! I think the tires are ok. That's what I thought it was at first but I had them checked and rotated and they're fine. Let me know what you think!