This case study showcases how iASYS engineered a Custom Belt Durability Test Rig for electric vehicle (EV) transmission validation. The solution featured a fixed and movable dyno system, multi-directional adjustable idler post, and flexible pulley adaptations to meet diverse OEM needs. With precise torque control, real-time load monitoring, and advanced thermal management, the rig enabled 1000+ hours of reliable testing, reduced vehicle-level testing efforts, and accelerated product development by 20–25%.