What was found
UPON GEAR RETRACTION ON THE AFTER TAKEOFF PHASE THE NOSE GEAR DID NOT RETRACT. WE HAD A --NOSE GEAR GREEN LIGHT-- WITH --DOORS AMBER LIGHT-- ACCOMPANNIED BY --AMBER GEAR LIGHT-- WITH EICAS --GEAR DISAGREE-- ANNUNCIATION. HIGH NOISE AND VIBRATION. UPON LEVEL OFF AND SLOWING DOWN TO 200 KTS, THE GEAR RETRACTED ON IT'S OWN. FACT 04MAR21 20:07 GSO REF W/O 79839 SEQ # 00002 WORKED PERFOMED BY HAECO VNMX EMPLOYEE # 3792377. REMOVED AND REPLACED NOSE LANDING GEAR DOWN LOCK ACTUATOR REF B757 AMM 32-34-02-4, ACCOMPLISHED NLG DOWN LOCK ACTUATOR INSTALLATION CHECK REF B757 AMM 32-34-02-4 STEP F. RMVD NOSE DOWNLOCK ACTUATOR PN: 273N1005-2 SN: 00203.