As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CRUISE FLIGHT WITH NG ABOVE 94%, OIL PRESSURE DROPPED TO 50 PSI. APPROACH WAS INITIATED AND PRECAUTIONARY LANDING WAS MADE WITH A NORMAL SHUTDOWN OF AIRCRAFT. OIL FILTER HOUSING/REGULATOR WAS CHANGED AND OIL PRESSURE RETURNED TO WORKING PROPERLY.