As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CLIMB OUT OR LEVEL OFF BELOW FL 260 AT 250 TO 280 KIAS THERE IS A VERTICAL VIBRATION IN THE AIRFRAME FELT IN THE FLOOR AND SEATS AND VISIBLE AS FWD AND AFT MOVEMENT IN THE YOKE. REMOVED AND REPLACED RT ELEVATOR TRIM TAB HORN BEARINGS IAW MM 20-10-08. OPS AND TRAVEL CHECK GOOD.