What was found
ON FLIGHT 3737 THE CREW REPORTED THAT ON ARRIVAL, AILERON YOKE ON THE FIRST OFFICER’S SIDE FELT VERY HEAVY, AND OR BINDING. THE FIRST OFFICER FELT RATCHETING IN BOTH LEFT AND RIGHT ROLL. THIS PROBLEM ALSO WAS ACCOMPANIED WITH EICAS CAUTION MSG "AP TRIM IS LWD" MULTIPLE TIMES INDICATING AP WAS HAVING DIFFICULTY TURNING. TRIM WAS NEUTRAL. TENSIONED LT AND RT AILERON FUSELAGE AND CONTROL COLUMN CABLES DURING AILERON RIGGING PROCEDURES IAW IAW AMM 27-11-00-820-801. COMPLIED WITH RIGGING AND TENSION CHECK PROCEDURES FOR ALL AILERON CONTROL CABLES IAW AMM 27-11-00-820-801. C/W FUNCTIONAL TEST OF THE AILERON CONTROL SYSTEM IAW AMM 27-11-00-720-801. NO DEFECTS NOTED. THE AIRCRAFT WAS RETURNED TO SERVICE.