Replaced the worn gear. Found another issue while replacing the gea. There is supposed to be a bushing pressed in to the top of the gear housing to hold the shaft in place. I must have had a manufacturing defect with mine though the bushing was just sitting on top of the other drive gears. It took some serious effort to get it up in the proper position (hammer). The mixer is better than it was when new now - it just kneaded bagels.