As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CRUISE AT FL 310, #4 ENG OIL QTY WENT FROM 3.5 TO ZERO IN APPROX. 15 MIN. OIL PRESS STARTED FLUCTUATING; OIL TEMP IN GREEN BAND (PERFORMED PRECAUTIONARY SHUTDOWN) WINDMILL RPNM 26%, N2 23%, OIL TEMP BELOW GREEN, OIL PRESS 10 PSI. EMERGENCY DECLARED & FLT DIVERTED TO ANC. AT ANC INSPECTED #4 ENG INLET & EXHAUST. NO FAULTS FOUND. INSPECTED ENG CORE - FOUND LOOSE COUPLING ON AFT ENG BEARING SCAVENGE LINE. INSPECTED LINE & COUPLING - NO ABNORMALITIES. RESECURED COUPLING. PERFORMED LEAK CHK & ENG RUN. NO LEAKS EVIDENT.