The paper presents integrated approach to Automobile Assembly Process. The approach describes about “Production Process Simulations” for New Products under development. This leads towards design verification during early prototype assembly process establishment for newly developed automobile vehicles and its control plan which regulates to final production practice.In recent years the Indian automotive business is expanding and with growing needs of faster new product development, the cycle time reduction becomes very crucial for environmental and economic reasons. The Lean production assembly and robust engineering processes are optimized in this approach.It's an advanced mechanism to identify process failures during final production setup. The experimentation has resulted towards establishing micro level study and critical stages to be captured well in advance for better planning. The actual verification of design at early stage builds confidence in New Product Development.This approach covers of all types of vehicle manufacturing, product mix, and deliverables of vehicle quality. The key achievement is by ensuring of significant & critical design parameters, engineering specifications, quality targets and customer perceived quality. The robust planning and decision making results in easiness of final product assembly line.This paper is an approach to create an integrated vehicle assembly process for New Product Development (NPD), in comparison with existing production process of vehicle assembly.