In the case of heavy duty engines, conventional cooling may often prove to be insufficient. Materials used within high-output engines are stretched to their allowed usage limits as the temperature nears maximum capacity. The use of oil coolers for heavy duty engine systems and their particular components, such as gearboxes, servo and hydraulic systems, significantly increases their lifespan. A distinction is made between air-cooled oil coolers and coolant-cooled oil coolers. In case of the latter, at the start-up, the coolant warms up faster than oil. Therefore, the oil reaches its optimal working temperature faster. As the engine reaches its working temperature, the heat is exchanged between the oil and the secondary coolant, helping the temperature to dissipate quicker. In such systems, coolers optimally regulate allowing the oil temperature. Depending on the application and system parameters (power output, working pressure), oil coolers are produced by different technologies: bar & plate, plate & fin, tube & shell and brazed plate.