Electric Vehicles and Plug-in Hybrids alleviate the energy crisis but pose a unique challenge for vehicle dynamics. Though significant developments in motor control strategy and energy density management are evolving, we face significant challenges in Torque Management with several ADAS features being integral part of the EV's/xHEV's. It demands high-fidelity physical and control model exchanges between electric-chassis, ride-handling, tire modelling, Steering Assist, powertrain and validate using 0D-1D platform. This paper explicates a unified strategy for improving overall vehicle performance by intelligently distributing and coordinating drive torque to enhance traction, stability, and drivability across diverse operating conditions through the co-simulation. Co-Simulation platform includes physical models in AMESIM, and control strategies integrated in MATLAB/Simulink. The platform features comprehensive representations of digital vehicle that requires detailed modelling of electric motor, transmission, differential, suspension, wheel dynamics, resistive forces (aerodynamic drag, rolling resistance) and road gradient effects enables accurate emulation of real-world vehicle behavior. Correlation of Test Vs. Simulation validates functionality and robustness of interaction between physical, basic and application software's control strategy. Digital Vehicle Validation includes traction-based torque limitation (Correlation: >90%), distributing propionate hydraulic and regenerative braking to improve braking performance, one-pedal driving and stoppage (Correlation: >85%), SOC influence on regenerative braking and smooth torque vectoring during dynamic behavior. Evaluation of diverse driving scenarios like, Gradient profiles (Uphill/Downhill/Curvilinear banking), Gradient-μ surfaces for real-world road profiles extracted from GPX/OSM data. Outcome of correlation details reduction of torque fluctuation, vehicle jerk during mode switching & stoppage, Anti-rollback, Aggressive Acceleration, Failure mode mimicking inverter failure in E-powertrain to construct a dynamic target to avoid lateral deviation.