As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT 5178 DIK-DEN PILOTS REPORTED RIGHT MAIN GEAR STAYED DOWN AFTER GEAR HANDLE SELECTED UP. CYCLED GEAR 3 TIMES BEFORE RIGHT MAIN FINALLY RETRACTED. LOUD GRINDING SOUND HEARD. INDICATED AIR SPEED ON 4TH GEAR RETRACTION WAS 140 KIAS. MAINTENANCE FOUND NO FAULTS IN THE RT GEAR SYSTEM. NOISE WAS FOUND TO BE COMING FROM NLG. MAINTENANCE REMOVED AND REPLACED THE NLG ACTUATOR. OPERATIONAL AND LEAK CHECK GOOD IAW 32-32-11. RII C/W 4.3.7. OPERATIONAL CHECK FLIGHT WAS SATISFACTORY.