Abstract: The reference has already conducted a shake table experiment about GMD with small gears. The experiment of this article was intended to install industrial steel gears whose accuracy grade was 7 M on the damper. The working performance of the damper was mainly studied when the device was stimulated by simple harmonic displacement. In conclusion, the damper shows a characteristic defined as negative stiffness. At the beginning of working condition, the device presented a property of positive stiffness. The friction between the bearing and the support, and the mechanical interaction between the rack and gears are important factors, which have effect on the working performance of the damper. After analyzing the data of the new experiment, it shows that the collision between balls in the test, the rolling friction and inertia mass force of the rack are the interference factors that influence the value of resisting force. Finally, advices on how to improve this experiment method were proposed.