Abstarct: The aim of this project is to investigate the effect of the functional parameters of the 206-engine mounting on the dynamic stiffness. In this project, the effect of design variables such as preload, frequency, displacement and ethylene glycol on the dynamic stiffness of the passive hydraulic engine mounting has been studied using practical tests. To measure the dynamic stiffness of the engine mounting due to various vibrations imposed by the vehicle body, a dynamic loadcell is needed that can measure force fluctuations with acceptable response time and accuracy. As a result, in the first step of this project, a dynamic loadcell with a capacity of 20000 N has been designed and manufactured. By comparing the results with a reference calibrated loadcell, the accuracy and repeatability of the new loadcell results were ensured. Results show that the static and linear error of this loadcell is less than 1% with 0.4 N/mm standard deviation. In addition, using design of experiments method, the effect of design parameters on dynamic stiffness was studied. The results showed that all the tested parameters were effective in the results. In general, the priority of influence is related to preload, amplitude of displacement, interaction between displacement and frequency and frequency, respectively. In the case of only rubber engine mounting, the frequency has less effect than displacement and preload on dynamic stiffness. In this case, displacement has the greatest effect both in upstream and downstream of the engine mounting. When the engine mounting is a combination of rubber and fluid, increase of frequency can affect more on dynamic stiffness of the engine mounting. In this case, the forces are dependent on all other parameters like displacement, frequency and pre-load in the upstream of engine mounting. However, in the downstream, the effect of preload and frequency will be more effective than displacement. Finally, additional tests at higher frequencies (more than 10 HZ) showed that the presence of ethylene glycol in 206 engine mounting has a significant effect on dynamic stiffness and shock absorption.