As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER DEPARTING KPTN ABOUT 15 MINUTES OUT TRANSMISSION LOW PRESSURE LIGHT ILLUMINATED AND TRANSMISSION OIL PRESSURE WAS READING LOW AND ERRATIC. TRANSMISSION OIL TEMPERATURE WAS READING HIGH. PILOT LANDED IN A FIELD. UPON SHUTTING DOWN THERE WAS OIL ON THE SIDE OF AIRCRAFT. MAINTENANCE WAS FLOWN TO THE LOCATION AND DETERMINED THAT THE FREEWHEELING UNIT AFT SUPPORT SEAL HAD MIGRATED PARTIALLY OUT OF THE SEAL BOSS AND WAS LEAKING. AFT SUPPORT ASSEMBLY WAS REPLACED AND TRANSMISSION SERVICEABILITY CHECK PERFORMED WITH NO DEFECTS NOTED.