What was found
FLIGHT DIVERTED, DURING T/O ROLL CONTROL COLUMN WAS VERY STIFF DURING ROTATION AFTER TAKEOFF, CONTROL COLUMN WAS STILL STIFF AND VIBRATION WAS FELT DURING LT AND RT TURNS. NO VIBRATION IN NEUTRAL POSITION. VIBRATION WAS FELT WITH AND WITHOUT AUTOPILOT. STIFFNESS WAS FELT MOSTLY IN THE AFT MOVEMENT. ACCOMPLISHED FIM 27-30-00-810-806A AND FOUND ELEVATOR CONTROL COLUMN DAMPNERS NEED SERVICING. FOUND EXCESSIVE DIRT BUILD-UP ON AFU + AILERON LT AND RT FUSELAGE SECTOR, CLEANED AREA IAW MM 27-11-07. ALSO ACCOMPLISHED FORCE CK OF ELEVATOR CONTROL COLUMN AND FOUND WITHIN LIMITS IAW MM 27-31-01, ACFT OK FOR CONTIUED SERVICE.