What was found
(CAN) DURING LAST PART OF CRUISE FLIGHT, 2 HYD PUMP CAUTION ILLUMINATED. ASSOCIATED CHECKLISTS COMPLETED. THEN ON APPROACH NR 2 SYS HYD QTY FELL FROM .333 TO ZERO. IT HAD BEEN STAYING STEADY. APPROACH DISCONTINUED WITH ADDITIONAL CAUTION LIGHTS: NR 2 HYD PRESS, NR 2 RUD HYD, AND PTU FAIL, ALSO SHOWING THE ROLL SPOILER OB, AND OTBD SPOILER CAUTION ILLUMINATED WHEN BELOW 165KTS. MANUAL GEAR EXTENSION REQUIRED. MAINTENANCE REPLACED A FAILED NR 2 EDP.