Light Grinding Noise while Accerating
 

I have a 05 Pacifica AWD, there is a light grinding sound while accerating plus while turning left or right. When coasting at 50-60 kph and turning th3 wheel left or right there is no noise. It is difficult to duplicate the light grinding noise while stationary. I have a mech stethoscope and listened to the alternator bearing while running, There is a noise but it doesn't really change when engine is revved a bit. I also checked the belt tensioner and the same thing, no real difference. There is no additional noise when steering wheel is moved left or right while sitting. My quesion is can the acceratoring and left or right turning or the vehicle while moving put extra draw on the alternator or pretensioner causing the light grinding in one of these parts? It sounds like a bearing noise/grind but I can't be sure as I can't make the same noise while sitting. Any suggestions?

Thanks