What was found
(AIRCRAFT NOT GROUNDED) DIRTY SOCK SMELL/ODOR REPORTED ON DESCENT TO LAS THROUGHOUT THE WHOEL CABIN (PX NOTICE IS ALSO) CAPTIAN SMELLED IT VERY LIGHTLY IN THE FLT DECK / PERFORMED TC 21-000-001, SMELL CAN NOT BE REPRODUCED. PERFORMED T/C 21-000-002 THIS CLEARS M313 MDDR 220637. AT THE START OF LEVEL 3 TASK CARD, FOUND SMALL OIL LEAK COMING FROM BOTTOM OF LUBE MODULE GASKET SEAL. REMOVED AND REPLACED APU LUBE MODULE GASKET SEAL IAW AMM 49-91-45-000/400-003-A. LEAK CHECK GOOD. COMPLIED WITH TASKCARD 21-000-003 REF W/O 534074"