Abstract
In the case of the engine mounting layout, it's very important to prevent the coupled vibration of lateral and rolling mode for the isolation of engine vibration and shock torque. On the other hand, the lower natural frequency, which means the lower rolling stiflhess, is also necessary for the isolation of engine vibration, but it is limited in terms of spring rate in maintaining the fatigue life of solid rubber. Therefore, in this study, an air spring is newly applied to the actual engine mount system of a medium duty truck and many vehicle tests are conducted for checking its vibration isolation effect and its big displacement caused by engine shock torque. As a result, the engine vertical vibration level at 19.1Hz dropped below 1/5 in of the current vehicle installed with cushion rubber and the engine displacement by its big torque was within the limit
