to the occupant during start stop events and switches to a low elastomeric rate state during idle and drive events for improved powertrain isolation in a first exemplary embodiment shown in fig1 3 strut assembly 100 includes a first portion or housing 102 at a first end of the strut assembly that at least partially receives a second portion or shaft 104 that forms a second end of the strut assembly each end of the strut assembly includes an eyelet 110 the housing 102 includes an eyelet 110 and the shaft includes an eyelet 112 each eyelet 110 112 receives a rubber isolator or bushing 120 that includes a central metal shaft 122 the eyelets 110 112 with the rubber bushing 120 received therein provide for attachment to the chassis or cradle not shown and the powertrain not shown an expander 130 has a threaded inner diameter which engages with a threaded outer diameter of the drive screw 140 a motor 150 which can be either a basic dc motor or stepper motor for example rotates or spins the drive screw 140 thereby moving the expander 130 along the axis of the drive screw as the expander 130 is drawn toward the motor 150 a tapered outer diameter of the expander presses against a tapered inside diameter of a collet 160 received.