On the passenger front side it sounds like my tire is going flat, there is a thumping noise, the steering wheel vibrates and pulls to left. I had the car in the repair shop replacing the tension belt pulley, the harmonic balance pulley, and the mechanic said I needed to replace the front passenger tire and that should stop the thumping and steering wheel vibration. I just had new tire put on and it still makes the thumping noise, like i am getting a flat tire and the steering wheel still shakes. What else can it be?