What was found
AIRCRAFT 3020, ON SHORT FINAL, STRONG DIRTY SOCK SMELL/ FUMES. ODOR STARTED AT 5,000 FT. ODOR WENT AWAY AFTER LANDING. ENG 1&2 BLEED WERE ON APU OFF. ODOR ONLY PRESENT INFLIGHT DECK. SEEM TO BE COMING OUT OF AIR VENTS. CORRECTIVE ACTION: DETERMINED SMELL COMING FORM OIL LEAK. ENGINE FOUND RESIDUE FROM BOTH ENG FAN DISK SEALS. REPLACED FAN DISK SEALS. REPLACED RECIRCULATION FAN FILTERS. (LP 6397010)