As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING DESCENT, NR 4 ENGINE OIL PRESSURE DROPPED TO 32 PSI AND LOW OIL PRESSURE LIGHT CAME ON, QTY AND TEMP WERE OK. SECURED NR 4 ENGINE. REPLACED OIL PRESSURE RELIEF VALVE SEAT AND SPRINGS IAW DC8 MM CH 80. RAN ENGINE, OPS CHECK AND LEAK CHECKED GOOD IAW DC8 MM 79-00.