TruckSim software tools simulate and animate dynamic tests of cars, motorcycles, scooters, racecars, and trucks, using standard Windows PCs. The math models, based on 30 years of university research in vehicle dynamics, simulate braking, handling, ride, stability, and acceleration with high fidelity. Core models can be extended with other software such as Simulink. The internal toolbox of VS Command language adds a powerful run-time programming capability that allows users to write their own code into the solver by which to define new variables, import and export variables, perform basic math functions (including branching), or even add new differential equations. Real-time versions test hardware-in-the-loop (HIL). Engineers use driving simulators with CarSim to feel subtle aspects of performance.