What was found
GRD CREW REPORTED SMOKE COMING FROM INBOARD MAIN GEAR TIRE #1 SIDE ON FURTHER INSPECTION WE DISCOVERED AN UNKOWN FLUID ON THE INNER RIM AND TIRE (INBOARD #1 SIDE). REMOVED FROM SERVICE. CLEANED #2 WHEEL AND INSPECTED BRAKE FOR ANY DEFECTS WITH NONE FOUND. PRESSURIZED THE HYD SYSTEM AND APPLIED THE BRAKES SEVERAL TIMES. REINSPECTED THE BRAKE FOR ANY LEAKS WITH NONE FOUND. PERFORMED A FOLLOW-UP INSPECTION OF THE #1 BRAKE. FOUND THE L/H MLG #2 BRAKE LEAKING. REPLACED BRAKE IAW MTC 6324201. RETURNED TO SERVICE.