As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER TAKEOFF, RECEIVED "GEAR DIAGREE" MESSAGE WHILE GEAR WAS COMING UP THERE WAS BUFFETING NOISES FROM NOSE GEAR AREA, DECLARED EMERGENCY AND RETURNED TO DEPARTURE. EMERGENCY DECLARED. LUBRICATED NOSE GEAR LANDING IAW AMM 12-20-32. PERFORMED NOSE EXTRENSION & RETRACTION IAW AMM 32-33-00. OPS CHECKED GOOD.