As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
MODERATE TO SEVERE VIBRATIONS FELT IN AFT CABIN & FLT DECK FLOOR ON CLIMBOUT. VIBRATIONS SUBSIDED AT LEVEL OFF. CONDITIONS REAPPEARED ON SUBSEQUENT FLIGHT. ACCOMPLISHED ELEVATOR INTEGRITY CHECKS. ALL 4 SERVOS REQUIRED ADJUSTMENT TO .5 DEGREES NOSE UP. FREEPLAY CHECKS ALL WITHIN LIMITS USING DIAL INDICATOR.