As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTED VIBRATION AND NOTICED THAT THE MAIN GEAR INDICATIONS WERE STILL ILLUMINATED. CREW LEVELED OFF AT 5000 FT, RAN QRH AND F/A CONFIRMED THAT THE GEAR WERE STILL DOWN. CREW DECLARED AN EMERGENCY AND RETURNED TO PIT. DURING APPROACH THE LT GEAR WENT UP AND SHORTLY AFTER THE RT GEAR WENT UP. CREW SELECTED GEAR DOWN AND ALL GEAR WENT DOWN AND LOCKED NORMALLY. CREW LANDED AND TAXIED TO GATE WITHOUT INCIDENT. MAINTENANCE TROUBLESHOT TO A BAD LANDING GEAR SELECTOR VALVE AND R & R VALVE AMM. ACFT IS GOOD FOR SERVICE.