As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PILOT REPORTED GEAR WOULD NOT CYCLE DOWN. GEAR WAS PUMPED DOWN MANUALLY. FLUID WAS OBSERVED LEAKING FROM LEFT HYDRAULIC FILTER HOUSING. HOUSING WAS REMOVED AND IT WAS DISCOVERED THAT THE LAST FEW THREADS ON THE HOUSING SIDE HAD CRACKED THROUGH. HOUSING AND O-RING WERE REPLACED AND SYSTEM SERVICED AND FUNCTIONALLY TESTED. (X)