Sloshing refers to the highly nonlinear movement of any liquid inside an object where the dynamic forces of the liquid can interact with the object to alter the overall system dynamics significantly. The purpose of this paper is to design and simulate the 3-D geometry of a fuel tank using the volume of fluid (VOF) method considering multi-phase fluid flow approach predicting fuel slosh movement at a specific capacity within a definite fixed volume. The splash of gasoline inside the partially filled fuel tank when subjected to sudden deceleration can be modeled, analyzed and effectively controlled by reducing pressure intensities inside the tank walls using a coupled fluid structure interaction at a common interface within the fuel tank through commercial CFD codes . This study is concluded by comparing two types of geometries using computational simulations inside the fuel tank considering 40% of fuel and 60% of air inside a 40 liters fuel tank, thus predicting the effect of sloshing forces and moments inside the tank structure considering longitudinal acceleration fields. The model is discussed and results are presented. In addition, this paper can be referred as a detailed guideline for analyzing sloshing phenomenon within a fuel tank using CFD simulations for effective fuel tank design in case of LCV's  which will be useful in product engineering and vehicle integration within automotive industry.