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The objective of this work is to evaluate the influence of a series connected spring deflection rate with a hydraulic vibration damper on the dissipative forces of the damper and the dynamics coefficients in the first level of the rail vehicle spring suspension. The object of research is а single-axle three-mass model with two spring suspension levels which corresponds to a four-axle section of an electric freight locomotive. The vertical vibrations of the rolling stock car body, bogies and wheelsets are simulated with a random kinematic disturbance which is the rail irregularities. These simulations perform with two design variants of the spring suspension stage: with a conventional and an elastic-protected hydraulic damper. The simulation also takes into account the elastic and dissipative properties of the track under the wheelset. The perturbation was determined by expressions of the spectral densities of irregularities separately for the low-frequency and high-frequency ranges. The solution of the vibration equations is performed in the frequency domain with the determination of the real, imaginary and amplitude frequency characteristics of the dissipative forces of conventional and elastically protected hydraulic vibration dampers linking the kinematic perturbation with a change in the forces of these dampers. The effectiveness of series connected spring with a hydraulic vibration damper was verified based on a study of the dynamic properties of a simplified three-mass model of a locomotive with a standard and elastically protected vibration dampers. In addition, based on a study of random processes of vertical vibrations of such a model, the values of the dynamic quality parameters were determined, as well as the maximum dynamic forces acting on the dampers. Based on the calculation results, conclusions were made about a significant decrease in the dynamic forces in the elastically protected damper compared to the standard one with an insignificant deterioration in the dynamic quality parameters, which in both calculation options do not exceed their permissible values. It is recommended that the final conclusions be made after solving the problem of optimizing the parameters of the spring suspension on a full-size model of the vehicle.