As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING A GROUND RUN IN PREPARATION FOR A FERRY FLIGHT, THE PILOT FELT A SIGNIFICANT VIBRATION IN THE AIRFRAME ACCOMPANIED BY AN ABNORMAL NOISE AND MGB CHIP CAUTION LIGHT. THE PILOT PERFORMED A NORMAL ENGINE SHUTDOWN AND INFORMED MAINTENANCE PERSONNEL. UPON REMOVAL AND DISASSEMBLY OF THE BEVEL REDUCTION GEARBOX AND EPICYCLIC REDUCTION GEARBOX, A SINGLE CRUSHED TOOTH WAS NOTED ON THE RING GEAR ALONG WITH A SIGNIFICANT AMOUNT OF METALLIC FLAKES WITHIN THE SYSTEM.