What was found
ON FLIGHT 3116 CREW REPORTED AFTER RETRACTING LANDING GEAR CAPTAIN AND FLIGHT ATTENDANT FELT AND HEARD LOUD THUMPING NOISE 4 TIMES. CREW ALSO NOTED LEFT RUDDER PEDAL VIBRATED. CREW DECLARED AN EMERGENCY AND ELECTED TO RETURN TO FIELD. AIRCRAFT REMOVED FROM SERVICE. PERFORMED TROUBLESHOOTING IN REF TO AMM 32-61-01 AND CMC DOWNLOAD IAW AMM 45-45-00 AND DETERMINED RIGHT MAIN LANDING GEAR UP LOCK PROX SWITCH TO BE FAULTY. REMOVED AND REPLACED PROX SWITCH AND PERFORMED VIBRATION WORK CARD IAW W/C 12-200-01, NO DISCREPANCIES WERE FOUND. AIRCRAFT AWAITING FCF.