As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CMH/BOS - FLT 1620 - AIR TURNBACK, IN-FLIGHT SHUTDOWN. ENGINE 2 LOW OIL PRESSURE LIGHT ILLUMINATED WITH PRESSURE ERRATIC. OIL TEMPERATURE AROUND 10. SHUT DOWN ENGINE. FOUND FERROS METAL IN THE MAIN ENGINE OIL FILTERS. REMOVED AND REPLACED ENGINE. (X)