Why is my Kenmore Coldspot (106.51783 410) making a high pitched squea

The squealing noise only happens at the start/end of some type of cycle so it's not constant and often wakes us up in the middle of the night. It seems like it's possibly the evaporator fan (and/or motor) as the noise is coming from the top part of the freezer. When the refrigerator door is open, you can also hear it screeching from the air filter box which we initially thought was the issue but it's louder on the freezer side. We've had no issues with frost or lack of cooling, just maybe some more condensation than normal in both fridge and freezer. This same noise happened last year, but after a power outage and the unit being off for a few hours the noise stopped.