The South African railway industry is in the process of revamping its fleet of rolling stock to cope with technological advancement. The paper presents the result of the reliability analysis, failure cost and factors affecting the performance of the electric locomotives operating between Kimberly and Swartkops. The research used field reports and financial reports to collect secondary data. The findings show that the fleet had an average of 71% reliability, and there was a direct correlation between the increase in the fleet size and number of failures. The result shows that the locomotives experience a high number of failures during the early days in operation and decrease over time. The accidents were identified as the main drivers of the maintenance cost and cost of quality accounted for 17% of the total cost of maintenance over 17 months. The environment where the locomotives are operating was identified to have the highest impact on fleet reliability. The research recommended improvement in the commissioning system to include the process to provide feedback to the production line. It is also recommended that the case study company should look at the possibility of initiating regular inspections to identify damages due to environmental factors.