Abstract: In engineering practice, it is inevitable that parametric uncertainties exist in the powertrain mounting system (PMS) of a vehicle and there is simultaneously a certain correlation and independence between the uncertain parameters. In this paper, the multidimensional parallelepiped model (MPM) is introduced to deal with the case of the co-existence of the system parameter correlation and independence, and a method of uncertainty analysis of the inherent characteristic of the mounting system is proposed by combining the Monte Carlo method. The analysis procedure of the proposed method is presented as well. The numerical analysis results of a mounting system show that the proposed method can effectively deal with the correlation and independence of the uncertain parameters of the system. Compared with the interval methods without considering parameter correlation, the proposed method can obtain more reasonable interval responses of natural frequencies and decoupling rates. Furthermore, for the given investigated model, the stiffness correlation of the left and right mounting points has obvious influence on the system inherent characteristics, which should be paid a special attention in the process of design and research

Key words: powertrain mounting system, multidimensional parallelepiped model, natural frequency, decoupling ratio, uncertainty analysis