What was found
(CAN) PILOT REPORTED THAT THE RT MLG DID NOT LOCK ON INITIAL GEAR DOWN SELECTION ON THE LAST 2 LEGS. ACFT WAS FERRIED TO BASE WITH GEAR DOWN AND TROUBLESHOOTING STEPS PERFORMED. PROBLEM WAS REPEATABLE ON JACKS UNTIL THE RT MLG STABILIZER BRACE WAS LUBRICATED. ROOT CAUSE OF INSUFFICIENT GREASE, COMBINED WITH AN OVER TORQUE IN THE LOCK LINK APEX JOINT CAUSING EXCESSIVE FRICTION IN THE LOCK LINK ASSY AOM 557 ISSUED.