What was found
GEAR DISAGREE NOSE APPEARED IN CRUISE WITH LOUD BANG & HASH MARKS ON NOSE GEAR INDICATION. TOOK OFF FROM KPGD NORMALLY AND ALL GEAR RETRACTED WITH NORMAL INDICATIONS. CLIMBING THROUGH 39300 FOR 40000 FT FOR CRUISE, HEARD A LOUD BANG FROM THE NOSE & THE HASH MARKS APPEARED OVER NLG INDICATIONS & GEAR DISAGREE NOSE CAS MESSAGE APPEARED. LEVELED AT 39000 AND RAN GEAR DISAGREE N QRH, WHICH THEN REFERENCED US TO LANDING GEAR WILL NOT RETRACT QRH. DECIDED TO CONTINUE TO CRUISE TO PIT AT 39000 & RUN MLG NOT RETRACT QRH ON DECENT, BELOW 18000. THROUGHOUT CRUISE HASH MARKS REMAINED & GEAR DISAGREE N CAS MESSAGE REMAINED. DESCENDING THROUGH 29700 FOR KPIT (APPROX 2101Z TIME) ACTIVATED SPEED BRAKES TO MAINTAIN SPEED. ON ACTIVATING SPEED BRAKE, HEARD ANOTHER LOUD BANG FROM NLG & NOSE INDICATION SWITCHED FROM HASH MARKS TO UP, & GEAR DISAGREE CAS MESSAGE DISAPPEARED. CONTINUED DECENT TO BELOW 18000 & LOWERED GEAR EARLY. GEAR EXTENSION NORMAL & HAD 3 GREEN. LANDED & TAXIED NORMALLY & POST FLT INSPECTIONS DID NOT REVEAL ANY OBVIOUS ANOMALIES. INSPECTED UPLOCK HOOK NLG GEAR SERVICING & NLG BRACKETS & FOUND NO DEFECTS. PERFORMED GEAR SWINGS WITH NO DEFECTS. DOWNLOADED ARES & SENT TO MANUFACTURE & THEY RECOMMENDED REPLACING NLG UPLOCK SWITCH DUE TO FAILURE R & R NLG UPLOCK SWITCH IAW MM 32-32-10 & PERFORMED LANDING GEAR ADJUSTMENT TEST IAW MM 32-00-00 OPS CHECKED GOOD. ORIGINAL SUBMISSION DATE: 12/15/2023