A shock isolator is arranged between two automated coupler parts in a vibration testing unit. When the coupler parts are engaged and coupled during vibration testing of a component, the shock isolator is disabled, and when the coupler parts are disengaged and decoupled after vibration testing, the shock isolator is activated to absorb excess shock energy and prevent shock transfer between the coupler parts that would damage the test component. The shock isolator includes a bushing that is inserted in a lower part of the two automated coupler parts and a compressive fit rod that is press-fit into the bushing. The bushing has a chamfered volume and the compressive fit rod has a corresponding compressible volume that is displaced into the chamfered volume to disable the shock isolator. After vibration testing, the compressive fit rod is expandable to a regular shape to activate the shock isolator.