What was found
(REF NR:MDR06-090) MAIN GEARBOX PN 6435-20400065, SN A6-011 WAS REMOVED DUE TO FINDINGS OF FERROUS METAL IN THE OIL SCREEN AND FILTER. UPON DISASSEMBLY AND TEAR DOWN, THE SOURCE OF THE FERROUS METAL WAS DISCOVERED TO BE COMING FROM GHE SECOND STAGE INPUT ALIGNMENT BEARING PN SB 2151-1, SN EAC18170. THE SB2151-1 BEARING CRACKED THROUGH THE ENTIRE INNER RACE AND CAUSED SUBSEQUENT CONTAMINATION OF THE MAIN GEARBOX, AND DAMAGE TO THE SECOND STAGE PINION PN 6435-20457-104, SN 333 ALIGNMENT BEARING JOURNAL. THE CRACKED INNER RACE WAS SENT TO THE MFG. PROBABLE CAUSE: UNKNOWN. (K)