As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN)WHILE REMOVING COMBINING GEARBOX CHIP DETECTOR, ALL OIL DRAINED FROM THE GEARBOX. THIS SHOULD NOT HAVE HAPPENED AS THE CHIP DETECTOR IS A SELF SEALING TYPE. THE HOUSING WAS REMOVED FOR INSPECTION AND THE CHIP DETECTOR PLUG AND SPRING WERE MISSING. CHIP DETECTOR PLUG AND SPRING WERE FOUND IN THE GEARBOX AFTER DISASSEMBLY OF THE GEARBOX.