Steering Vibration Noise

I am thinking about purchasing this particular A4 and the only thing that I can find wrong with is this vibration in the steering. The whole car seems to vibrate and jitter. It happens on sharp turns when the car is moving the steering wheel postion is towards the end of travel each way. Like a u-turn would be a good example. Works great if the car is sitting still there is no noise or vibration moving the steering wheel both ways through the whole range of travel. It almost seems drivetrain related. Let me no if anyone else has had this problem.