The design process for railway vehicles in Europe is usually consecutive. Optimizations from different disciplines ideally build on the results of the preceding step, but direct linking and mirroring of the findings of different disciplines only takes place to a limited extent. The end product is thus a railway vehicle built from local optima and may differ significantly from the global optimum, because optimisation potentials are not exhausted. The lightweight design of vehicles is becoming more important due to the increasing application of alternative drive systems and the goal of maintaining high payload capacity while optimizing energy efficiency. In order to achieve a global optimum in terms of lightweight potential, it is necessary to interweave the findings of different disciplines. In this paper, an algorithm-based method for interweaving the (quasi-)static design for a lightweight-optimized car body structure (topology optimization) with the findings from the dynamic investigation of an entire railway vehicle based on a multi-body-simulation (MBS) is presented. At an early stage, findings from the MBS are linked with the topology optimization and consequently to the development of the mechanical design. Through this, a design can be derived that best fulfills the dynamic requirements as well as the (quasi-)static boundary conditions in a global optimum with regard to a best possible exploitation of the lightweight potential of the mechanical car body design. Based on the design-relevant boundary conditions, as well as consideration of the manufacturing requirements, a finite-element (FE) model of a car body is automatically divided into segments with an algorithm and then different topology optimizations of the whole car body are performed, where possible requirements are considered. Each segment is then automatically evaluated in terms of its structural loads and optimized mass distribution and assigned to a design from a previously defined design catalog, which contains possible construction methods. This is necessary because the proposed design should be manufacturable. By transforming a theoretically optimal structure in terms of lightweight design to a manufacturable structure, the expected masses, centers of gravity and mass inertias of the segments can be calculated. These serve as input data for the MBS. With the aid of the MBS, a vehicle-dynamics evaluation of the previously defined mass distribution can then be carried out, with running safety, comfort and infrastructure load being examined as evaluation criteria. The running behavior is decisively influenced by the mass distribution in the car body, whereby the different variants of topology optimized car bodies can cause different running behaviors. To ensure comparability between the optimized variants the same bogie is used for all vehicle dynamic investigations. The various body variants are evaluated on the basis of the vehicle dynamics analysis so that, on the one hand, variants with critical vibration or running behavior are excluded and, on the other hand, variants with advantageous dynamic properties are further considered and processed. In this way, vehicle dynamic optimization is already included in the design phase. By assigning real designs and mass data to the individual algorithm-based segments of the topology-optimized structure, MBS can already be performed in the early conceptual phase. Thereby the risk of complex changes to the mechanical structure or packaging later in the development process is minimized. By adapting boundary conditions or packaging in the structural optimization, the dynamic behavior of the rail vehicle can already be considered in the lightweight-optimized structural design and the rail vehicle can be optimized in terms of both lightweight design and dynamic behavior. With respect to these two disciplines, a global optimum is achieved through the presented algorithm-based method and the resulting interweaving of different simulative processes in the early conceptual phase.