As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
IAH - FLT 464 - THE NR 1 ENGINE LOST OIL QUANTITY IN FLIGHT. THE OIL PRESSURE GRADUALLY DROPPED TO 20 PSI. THE ACFT WAS DIVERTED TO BNA AS A PRECAUTIONARY MEASURE. MAINTNANCE FOUND O-RING ON HIGH PRESSURE SHAFT OF NR 1 ENGINE LEAKING. THE O-RING WAS REPLACED. THE NR 1 ENGINE WAS RUN AND OPERATION CHECKED GOOD WITH NO LEAKS NOTED. (W)