Annually locomotive-building plants, equipment suppliers and service companies develop organizational and technical measures aimed at improving the reliability of products. Thus, within the framework of the contract for the supply and maintenance of electric locomotives of the ERMAK series, a number of corrective measures have been implemented in more than thirty directions, many of which have achieved a positive result. However, during the long-term operation, more and more new hidden technical defects are revealed, and in rare cases, the measures taken are not enough. The manifestation of systemic inconsistencies is random in nature, thereby they negatively affect the dynamics of the average daily mileage and the linear mileage completed over the entire life cycle, causing unpredictable fluctuations, and as a result, the organization of service planning and budgeting to support the life cycle of locomotives. Therefore, there is a need to develop a model for a more accurate forecast of the average daily mileage for a long period, considering the impact of system inconsistencies and corrective measures to improve the reliability of nodes. The article uses the Pareto principle to analyze system malfunctions of locomotives manufactured by PC NEVZ LLC for the period of operation from 2018 to 2021, analyzes the dynamics of the average daily mileage of the locomotive fleet of the Far Eastern Traction Directorate with the use of a statistical and analytical method, analyzes the impact of failures on the average daily mileage using the Fourier time series forecasting method. On the example of malfunctions of power current-carrying buses of a rectifier-inverter converter and malfunctions of latches of a high-voltage vacuum circuit breaker, the influence of malfunctions of critical nodes is evaluated.