As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE DRAINING OIL FROM MAIN TRANSMISSION TO REPLACE THE FREEWHEELING UNIT FOR OVERHAUL,A METALLIC PIECE WAS FOUND AT THE DRAIN PORT. PREVIOUSLY THIS TRANSMISSION HAD CHIP LIGHTS AND THE SERVICEABILITY CHECKS REQUIRED BY THE MANUFACTURES MAINTENANCE MANUAL WERE CARRIED OUT WITH NO FURTHER DIFFICULTIES. TRANSMISSION HAS BEEN REMOVED AND SENT FOR EVALUATION AND REPAIR.