I tried taking apart the auger and ice box assembly multiple times. I realized one washer was missing, so I replaced it with the correct part from this website. It didn't fix it. I tried many crazy ideas, including reversing the order of the blades in the auger. I then thought it was the motor assembly becoming weak over the years. Then, I finally discovered the problem - the rotating shaft that coupled with the auger had gotten pushed down maybe 1/4 of an inch or less. Perhaps someone was putting the ice box back in but forced it down too hard. Anyway, I manually pulled up the shaft and now it works fine.