One problem related to differential unit has been reported for the 2000 Subaru Legacy. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2000 Subaru Legacy based on all problems reported for the 2000 Legacy.
Summary the transmission failed with 45,926 miles. It was a catastrophic failure caused by a manufacturing defect in the differential assembly rack and pinion. The gears have microscopic cracks and the teeth broke off at 30-35 mph. The cracks are visible to the naked eye. The transmission shop that repaired the vehicle, said it was the second Subaru that had a similar failure. I have asked Subaru to review the case. Subaru indicated the failure was due to preventive maintenance issues not a product defect and refused to absorb any of the repair costs of $1695. I have the parts that failed and I will re-contact Subaru, request that a zone rep look at the failed components, and review the case again.