This study presents a comprehensive evaluation of the residual life of the ADM-1 diesel assembly rail service car, focusing on structural integrity under dynamic loading conditions and the effects of corrosion. Utilizing a Finite Element Analysis (FEA) model and validation of the model by experimental testing, the research work identifies critical stress points in the vehicle’s frame that significantly influence its lifetime. Key findings reveal that corrosion rates must remain below 14% for transverse beams and 18% for longitudinal beams to ensure safe operation. Furthermore, the integration of predictive maintenance strategies enhances the accuracy of remaining useful life (RUL) assessments. This work contributes valuable insights into sustainable railway management practices, underscoring the necessity for ongoing structural assessments and innovative maintenance approaches to extend the operational lifespan of rail service vehicles.