As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CRUISE, THE NR 4 ENGINE BEGAN LOSING OIL QUANTITY AND WHEN PRESSURE BEGAN TO DROP THE ENGINE WAS SHUTDOWN. THE AIRCRAFT DIVERTED TO NRT WHERE AN UNEVENTFUL THREE ENGINE LANDING WAS MADE AND 165,000 LBS OF FUEL WAS DUMPED. METAL WAS FOUND ON THE MAG PLUGS AND THE ENGINE WAS REPLACED.