What was found
(CAN) PILOT REPORTED THAT WHEN AUTOPILOT WAS DISCONNECTED ON APPROACH ELEVATOR CONTROL WAS VERY HEAVY. PILOT ASKED CO-PILOT TO CONFIRM. BOTH WERE IN AGREEMENT THAT AIRCRAFT WAS VERY HEAVY ON THE PITCH CONTROL. AN UNEVENTFUL LANDING WAS COMPLETED WITH BOTH PILOTS FLYING AIRCRAFT DUE TO HEAVINESS OF CONTROLS. ONCE ON GROUND, IT WAS AGAIN CONFIRMED THAT ELEVATOR CONTROL FELT HEAVY. NOISE COULD BE HEARD WHEN ELEVATOR CONTROL WAS MOVED. NOISE WAS ISOLATED TO ELEVATOR AUTO PILOT SERVO, WITH SERVO MOTOR REMOVED CAPSTAN DRIVE GEAR DOWELS (QTY 6) WERE FOUND SHEARED. THE ELEVATOR SERVO MOUNT WAS REPLACED AND THE ELEVATOR CONTROL SYSTEM INSPECTION WAS COMPLETED FROM NOSE TO TAIL WITHOUT ANY OTHER ANOMALY FOUND.