In trains, radiator systems are used to regulate the temperature of the engine, allowing it to operate at a consistent temperature without overheating - no matter the outside climate.

Trains manage heat through several advanced cooling systems, primarily focusing on the engines (in diesel-electrics) and the braking systems. Diesel-electric locomotives use massive radiator banks with powerful fans to dissipate heat from the engine's coolant, similar to a car but on a much larger scale. For the wheels and brakes, modern trains utilize regenerative braking, which reverses the electric motors to slow the train down, converting kinetic energy back into electricity for the grid instead of just creating friction. However, when physical friction brakes are needed, they generate immense heat; these are cooled naturally by airflow as the train moves. High-speed trains also feature sophisticated air-conditioning units for the cabin, often located on the roof or under the chassis, which use heat exchangers and refrigerant cycles to maintain a stable internal temperature against the friction and external heat.