As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLIGHT DIVERTED DUE TO IFSD OF NR 1 ENGINE. [SUP 05-24-07] THIS OCCURRENCE WAS DUE TO ANGLE GEARBOX BEARING FAILURE CAUSED BY EXCESSIVE VIBRATORY STRESS. THIS IS BELIEVED TO HAVE BEEN THE RESULT OF AN IMPROPER BALANCING OF THE LOWER TOWER SHAFT WHICH COULD HAVE OCCURRED DURING INITIAL STAGE OF MANUFACTURE BY THE OEM.