What was found
NR 4 PROP LOW OIL LIGHT CAME ON WITH RPM OUT OF LIMITS, SHUT DOWN ENGINE IN FLIGHT AND AT THE SAME TIME NR 3 ENGINE PROP LOW OIL LIGHT CAME ON. DECLARED EMERGENCY AND LANDED WITHOUT INCIDENT. FOUND NR 4 PROP LEAKING EXCESSIVELY AT NR 1 AND NR 2 BLADES, SERVICED ALL FOUR PROPS AND PERFORMED ENGINE RUN, NR 4 PROP HAS SLOW LEAK. PREPARED AIRCRAFT FOR MAINTENANCE FERRY TO ANC, AFTER 1.3 HR INTO FLIGHT, NR 4 PROP LOW OIL LIGHT CAME ON AND NR 3 PROP LOW OIL LIGHT CAME ON AFTER 3.3 HR INTO FLIGHT. AIRCRAFT LANDED WITHOUT INCIDENT. REMOVED AND REPLACED NR 4 PROP ASSEMBLY, NR 3 PROPELLER AND PUMP HOUSING, ALL WORK DONE IAW SAT J/C 6101, 6101-1 AND OPS CHECKED PER J/C 7101 AND 7101-2.