Noisy Kenmore Elite Model #66513123K702?

I have a Kenmore Elite Model #66513123K702 that was purchased in mid 2009. All was going well, dishes were adequately cleaned, no electrical issues, etc. until yesterday when it became quite noisy during cleaning, not filling. I checked the upper and lower filters and they are clear. Everything seems to be draining well. Is it worthwhile to check the food chopper assembly? If so, is there a step by step guide to doing so that someone can link for me. I have looked, but I have not found one online for this particular model. What are some other possible causes and solutions for the suddenly noisiness? Thanks for any and all help. It is much appreciated.