I have 2006 pontiac g6. It makes a loud growling noise while driving and gets worse at higher speeds. Firestone and another mechanic both said I needed to replace a wheel bearing. Today, a different mechanic told me that it was the rack and pinion because of the play in my steering wheel and check under the car. He told me that the noise was most likely the right tire rubbing. And that a balance and alignment will fix it. Which do you think is more like problem? What should I do?