Understanding the phenomena and their response to various issues in today’s engineering such as aerospace, hydraulics, and fluids is of great importance. Some problems cannot be solved by analytical methods; therefore, numerical solutions should be used to investigate how fluid behaves. Many softwares have been developed in this area, most of them are owned by business companies. But with the ever-expanding Open-Source softwares, the Computational Fluid Dynamics ones have also grown. One example is the OpenFoam Software. One of the problems in numerical softwares is the proper way of producing the appropriate computational grid. The quality of the computational grid greatly affects the accuracy and cost of the solution. Choosing the appropriate grid type, how large and small they are and how to integrate these features with the complex physics is a timeconsuming task. This complexity is significantly enhanced for aerodynamic and turbomachine models. In this study, an automated approach to create suitable numerical grids for automotive aerodynamics is developed. Problem validation with the most commonly used model AhmedBody done. Then geometric models of different types of cars are first designed for different automobile categories such as sedans, pickups, etc. in a solid modeling software. Then using the OpenFoam Software and its grid generation tool namely the snappyHexMesh numerical grids are generated for these geometries. By studying and modifying the parameters of the OpenFom grid generator, suitable grids for these vehicles are achieved. A program has been developed to automate the process of grid generation and the flow solution. This program was used to generate the grid and solve the flow field around various Sedan, SUV, Coupe, Truck, Supermini, HatchBack,Off-road, Station wagon, and Van vehicles.