This paper presents the design and implementation of a full-stack web application to advance predictive maintenance and fleet performance monitoring in smart city frameworks. The application combines management of real-time data collection, predictive analytics, and a user-friendly interface, allowing fleet managers to optimize maintenance schedules and improve operational efficiency. Leveraging 5G technology for high-speed data transmission, the system enhances connectivity and facilitates seamless communication between fleets and infrastructure. It delivers actionable insights on fleet performance and maintenance requirements, addressing challenges in data extraction across different fleet types. Planned enhancements include integrating IoT sensors and virtual reality modules for advanced training scenarios, extending the platform’s capabilities further. This study showcases the role of advanced technologies in improving fleet management, contributing to sustainable urban mobility and the development of smart cities.