What was found
WHEN MLG WAS SELECTED UP, RT MAIN & NOSE GEAR INDICATED UP, LT MAIN INDICATED AMBER, THEN RED. RAN QRH PROCEDURE FOR "LANDING GEAR DOES NOT LOCK UP". ALL 3 GEAR INDICATED DOWN & THEN WHEN GEAR SELECTED UP, LT MAIN STAYED DOWN, NOSE & RT MAIN INDICATED UP. GEAR THEN CYCLED DOWN WITH ALL 3 DOWN INDICATIONS. DURING FLT A SLIGHT PULL TO LT NOTED WITH LT MAIN RED HASH MARKS AND DOWN. REMOVED LT MLG ACTUATOR & INSTALLED REPAIRED ACTUATOR. PERFORMED SATISFACTORY, GEAR SWINGS (APPROX 20), LEAK CHECKS, INTERFERENCE CHECKS & ALL OPS CHECKS ON LT MLG. ALL MLG CYCLED NORMAL WITH 3000 PSI HYD PRESS. FROM HYD. MULE. ALL MLG INDICATIONS ON EICAS NORMAL. WORK PERFORMED IAW MM 32-10-20, 32-10-15, 32-10-10 AND CMP 321003.