What was found
DURING GEAR RETRACTION ON FLIGHT 3460, GEAR UNSAFE LIGHT ILLUMINATED, WOULD NOT EXTINGUISH. AIR RETURN TO DTW. RT MAIN GEAR UNSAFE INDICATION ILLUMINATED AFTER GEAR RETRACTION, CYCLED UNDER DIRECTION OF DTW MX. RT MAIN UNSAFE EXTINGUISHED. LT MAIN GEAR ILLUMINATED, CYCLED 5 TIMES UNDER DIRECTION OF MX LIGHT REMAINED ILLUMINATED. MAINTENANCE FOUND ICE AND SNOW SLUDGE ON MLG UPLOCKS, THAWED, CLEANED, AND LUBED UPLOCKS. PERFORMED OPS CHECK IAW AVRO AMM 32-30-00 501. DID SEVERAL GEAR SWINGS. NO DEFECTS NOTED AT THIS TIME.