I disassembled it and found a nylon gear that had launched itself against its steel counterpart. For 40 bucks I had a replacement part in 2 or 3 days, installed it, and it runs like a champ. My wife didn't want to have to replace a $400 to $500 machine, so this was the way to go. I would rather spend that money on a weekend trip than a new mixer:)
Thanks much guys.
Mark