As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
UPON LANDING IN MKE, THE TOWER NOTIFIED THE CREW OF SMOKE COMING FROM THE LEFT MAIN LANDING GEAR. THE AIRCRAFT WAS STOPPED AND PASSENGERS WERE EVACUATED. BRAKE TEMPERATURES WERE ALL IN THE NORMAL RANGE. UPON INSPECTION, THE LEFT INBOARD BRAKE HAD AREAS OF YELLOW FLUID ON IT. NO SIGNS OF HYDRAULIC LEAKAGE WERE FOUND ON THE BRAKE. THE LEFT INBOARD BRAKE WAS REPLACED WITH NO FURTHER DEFECTS NOTED DURING TAXI.