As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT LOST OIL IN FLIGHT, WAS ABLE TO MAKE IT TO ITS FINAL DESTINATION. THE AIRCRAFT LANDED SAFELY AT AN ALTERNATE AIRPORT. A MECHANIC AT THE AIRPORT HAD DISCOVERED THE TACH DRIVE HOUSING AND TACH CABLE HAD COME LOOSE. THE ENGINE WAS REMOVED AND RETURNED FOR DISASSEMBLY AND INSPECTION.