Air-cooled oil coolers are designed to be used where access to a power source is limited, such as agricultural and construction sites. Sometimes called heat exchangers, air-cooled oil coolers pass oil through a coil or core to cool the oil before it can enter the system. Keeping hydraulic oil cool helps extend system life by reducing wear and damage caused by excess heat. Heated oil causes excess wear on seals, surfaces, and other components, which can cause particulate buildup and damage components.