What was found
DESCENDING THRU 9000 MSL, 245K, ATTEMPTED TO EXTEND FLAPS TO 5 DEGREES, AT WHICH TIME EICAS INDICATED FLAPS FAIL. SLATS WERE FULLY DEPLOYED & FLAPS WERE EXTENDED LESS THAN 5 DEGREES. PER CHECKLIST, ATTEMPTED TO RESET FLAPS WITH NEGATIVE RESULTS. COMPLETED CHECKLIST & LANDED WITHOUT INCIDENT. BITE CODES ON FLAP CONTROLLER WERE 1, 2 & 7. CLEARED CODES & BEGAN TROUBLESHOOTING IAW MM 27-50-00. FOUND PDU FAILING CLUTCH CHECK IAW MM 27-50-00 & PDU HAD AN EXCESSIVE AMOUNT OF GREASE AT THE CONNECTION TO THE RT FLEX DRIVE. R & R FLAP PDU IAW MM 27-52-00 & CLEANED UP EXCESSIVE GREASE FROM RT FLEX DRIVE CONNECTION. VERIFIED NO BINDING AT LT & RT FLAP PANELS. VERIFIED ELEC & MECHANICAL RIG IAW MM 27-50-00. OPERATIONAL CHECKED GOOD.