Three problems related to differential unit have been reported for the 2001 Subaru Outback. The most recently reported issues are listed below.
Starting around 62k miles, I heard a whining noise from the front of the car. The noise got louder and higher with wheel speed. When I took it to a mechanic, they diagnosed a bad differential bearing, and informed me that the recommended fix was replacement of the entire transmission, including both differentials. When I went to the dealer to confirm this, they quoted me $6,000-$8,000 for the repair. I tried to get some relief from Subaru of America, since the powertrain warranty goes for 60k miles, but they were unwilling. This caused the value of my car to go to zero, since it's worth about $8,000 without the transmission problem.
I own a 2001 Subaru Outback. After hearing a whining noise in the front of the car, I took my car into my mechanic. He informed me that I probably needed to have the front differential replaced and referred me to the dealership. The dealership told me I needed the entire transmission replaced. Because the milage on my car was at 62,000 miles, the dealership would not honor my warranty because it only extended to 60k. Astounded that any car with only 62k miles on it would need its entire transmission replaced, I appealed to Subaru customer services and asked them to own up to the defect. They declined my request.
While driving 50 mph there was vibration in the center of the vehicle. Consumer took vehicle to the dealership, and technician determined rear differential unit needed to be replaced.