As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
IT WAS NOTICED THAT AIRCRAFT WAS TRAILING OIL & SMOKE FROM THE EXHAUST IN FLIGHT AND DID A LANDING AND INVESTIGATED. FOUND OIL ON TAIL BOOM AND EXHAUST TURBINE. GROUNDED AIRCRAFT. PREFORMED ENGINE CHANGE UP, AT LANDING SITE. SENT ENGINE FOR INVESTIGATION. IT IS DETERMINED THAT THE REAR BEARING WAS COKED AND CAUSED THE LABYRINTH SEAL TO LEAK. ENGINE WAS CLEANED TESTED AND SENT BACK AS SERVICEABLE.