As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SHORTLY AFTER DEPARTURE PILOT RECEIVED "XMSN OIL PRESSURE" WARNING LIGHT ALONG WITH AN INCREASE IN INDICATED PRESSURE. PERFORMED PRECAUTIONARY LANDING AND MAINTENANCE REPLACED THE TRANSMISSION OIL PRESSURE SWITCH. TRANSMISSION OIL PRESSURE RETURNED TO NORMAL AND WARNING LIGHT DID NOT COME ON. AIRCRAFT WAS REPOSITIONED TO MAINTENANCE FACILITY. TRANSMISSION OIL FILTER WAS PULLED AND NON-FERROUS METALLIC CHIPS WERE FOUND.