A test rig comprising a shaft system connected by a gear coupling and a dummy shaft system to transmit static torque was made for confirming the analytical method of torsional response presented in the first report. The analytical result and the experimental result were compared and their response curves show good agreement when the teeth of gear coupling contact at the back face. Furthermore the effect of angular acceleration on resopnse was investigated by changing the magnitude of the dynamic torque and the lubricant. When the magnitude of dynamic torque is relatively large and contact of teeth at the back occurs, the transient response curves change drastically during deceleration. However, during acceleration they do not change. If the clearance of coupling is filled with lubricant, the maximum transient response is smaller than that without lubricant when the angular velocity decelerates. But the maximum transient response with lubricant is almost the same as that without lubricant in acceleration.