As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CRUISE AT FL340 THE RT ENGINE FAN VIB INDICATED APPROXIMATELY 2.5 FOR 1 SECOND THEN FLUCTUATED CONTINUOUSLY AND WAS ABNORMALLY HIGH. THE CREW REPORTED SLIGHT YAWING DURING VIBRATIONS. THE FLIGHT DIVERTED TO DAY AND LANDED WITHOUT INCIDENT. AFTER TROUBLESHOOTING THE INDICATION SYSTEM AND FINDING NO DISCREPANCIES, MAINTENANCE LUBRICATED THE RIGHT ENGINE FAN BLADE TANGS. OPERATIONAL VIBE CHECK OF RIGHT ENGINE WAS GOOD. THE AIRCRAFT WAS RELEASED FOR SERVICE.