hello everyone. have a 03 silverado z71 ext. cab. during fast acceleration or while shifting from 1st -> 2nd and 2nd -> 3rd, there in a loud "pinging" noise in the rear it sounds. There is no play in either driveshaft and no vibration while cruising. Does anyone know if this could be the u-joints or the ring and pinion? Any other ideas?? please help!