A motor driven compressor had been experiencing periodic failures of the shim packs in its metal coupling. Strain gages and wireless telemetry were used to measure dynamic torque levels in the coupling and determine that there was a torsional resonance occurring very close to the system operating speed of 600 rpm. A torsional model of the driveline was correlated to match the test results and was then used to determine the appropriate size of internal compressor de-tuner that should be added to move the system away from resonance at operating speed.