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The theoretical fundamentals of dynamic analysis including modal analysis and random vibration analysis were described, and they have been applied in analyzing heavy truck frame. In order to understand the dynamics of the frames, the finite element model based on shell element was set up, modal analysis and random analysis based on road spectrum were implemented and dynamic or instrumentation test of the vehicle driving was conducted to verify the theoretical analysis. These results provided valuable theoretical basis and references in improving structural design of frame, guaranteeing stability, safety and comfort of vehicle operation. 