As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
EN ROUTE TO DEN, THE NR 3 ENGINE LOW OIL PRESSURE WARNING INDICATION ILLUMINATED. OIL PRESSURE AND OIL QUANTITY INDICATED ZERO. ACCOMPLUSHED PRECAUTIONARY SHUTDOWN OF THE NR 3 ENGINE. MAINTENANCE FOUND THREADS DETERIORATED IN GEARBOX CASE ALLOWING OIL LEAKAGE AT RETURN TUBE. REPAIRED THREADS AND RESEALED TUBE. SERVICED ENGINE OIL. TESTED ENGINE PER MM. ENGINE CHECKED OK. AIRCRAFT RETURNED TO SERVICE.