Why is the washer drum banging in the spin cycle?

I have a HE3t washer that is 11 years old (Jan 2004). In the spin cycle the washer drum seems loose and bangs and does not get to full spin speed leaving the clothes wet on cycle completion. Pieces of white fiberglass-like curved material are visible during the spin cycle and are getting into the washer drum with the clothes. Is this problem a minor, fixable problem or a more significant one requiring washer replacement? I found a website indicating it might be a snubber ring designed to minimize the noise and vibration during the washing cycle. Is a snubber ring white? Please share your expertise with me!