Turning speed vibrations on the motor DE increased significantly, with noticeable impacts at 1X turning speed in the time waveform. This suggested a possible coupling or bearing clearance issue.​

The CME recommended taking apart the coupling for inspection. While apart, a lift test should be performed on the motor shaft to check for excess bearing play.​

Upon inspection, the motor side of the coupling was found to be stripped, with the teeth completely worn down. The coupling was replaced, resulting in a noticeable drop in vibration levels.