As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CLIMBING THROUGH 15,000 FEET AT 290 KNOTS, EXPERIENCED AIRFRAME VIBRATION MOST NOTICEABLEY IN THE AFT CABIN. REDUCING SPEED REDUCED VIBTATION. AIRCRAFT RETURNED TO MSP UNDER DIRECTION OF MAINTENANCE CONTROL AND DISPATCH AND ACCOMPLISHED AN UNEVENTFUL LANDING. MAINTENANCE REPLACED FOUR ELEVATOR SERVO CONTROL ROD ENDS.