As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) DURING CRUISE FLIGHT CREW NOTED RT ENGINE OIL PRESSURE FLUCTUATIONS. FLUCTUATIONS CONTINUED SO FLIGHT CREW SHUTDOWN THE RT ENGINE IN FLIGHT AND RETURNED TO DEPARTURE AIRPORT. MAINTENANCE FOUND OIL LEAKING FROM THE ENGINE REDUCTION GEARBOX AT THE HYDRAULIC PUMP INPUT DRIVE HOUSING. THE SEAL, PN 3022375 WAS REPLACED AND TESTED SERVICEABLE.