This paper introduces an advanced multibody model of an articulated vehicle, including a multibody dynamics model of a tractor with a flexible semi-trailer. This study proposes a combination approach of Multibody Dynamics analyzing the rigid body motion and the Finite Element Analysis of the semi-trailer frame to estimate the displacement, stresses, deformation and dynamic loadings within a flexible body. The multibody dynamics model describes the physical relationship between the tractor and the flexible semi-trailer frame to extract the forces acting on joints and contacts between suspension components of the tractor and chassis frame at joints and the fifth wheel, which partially supports the semi-trailer payload. The methodology is applied to model the combination of a multibody tractor model and a flexible frame model simulated in typical driving scenarios using MotionView and HyperMesh within the HyperWorks environment. Finally, the graphical results of the simulations were generated, plotted as well asdiscussed in terms of modal analysis, static and dynamic stress, loading and force acting on the finite element model of a flexible semi-trailer frame. The analysis results from these simulations provide a comprehensive evaluation of the behavior of the vehicle frame, which can be used to assess the frame's durability and fatigue life under various driving scenarios.