What Is an Oil Cooler and its Main Purpose

 

An oil cooler is essentially any device or machine intended to cool oil, but in most instances people talk about it in the context of cars, trucks, and sometimes airplanes. In these settings the cooler basically acts as a small radiator that helps keep an engine cool by keeping the oil supply at a consistent temperature. Cooled oil helps keep the engine running smoothly, particularly during gear changes in very hot weather or on long-haul trips when things might otherwise have a tendency to overheat and break down. Not all cars and trucks use oil as a coolant, but those that do really depend on a working cooler in order to get good efficiency and performance.

Main Purpose

Automotive engines tend to be somewhat complex, and usually depend on a series of different combustions, heat sources, and temperature regulators in order to function properly. Oil coolers are most common in heavy-duty machinery that has a more industrial-grade engine. Trucks used to haul freight and large vehicles designed for off-roading are two common examples; some recreational vehicles (RVs) and airplanes have them, too, and they may even be found in certain motorcycle models. Race car drivers sometimes add them to sports cars to make them more efficient, too, and to improve their fuel combustion times.

A transmission oil cooler is often considered essential in high-strain situations because a transmission's lubricating fluid heats up with each gear change. While not crucial for highway driving when vehicles more or less stay within a few gears, transmission coolers can markedly improve the performance and longevity of transmissions that are subjected to a great deal of stress. Overheated transmission oil can lead to slower gear shifts, worn seals, lower mileage, and, ultimately, premature failure.

Even though the main job is to cool and lubricate the engine, this part can also act as an important coolant for a number of other parts. A motor's bottom end, which includes parts such as the crankshaft, bearings, camshaft, rods, and pistons, is also cooled only by engine oil, for instance, and this cooling can impact overall performance just as much as it could in the engine itself.

Types

Engine oil cooler design can generally be split into two types. Tube and fin models are the first, and are designed so that oil circulates through cooler lines that surround the engine. As the oil moves away from the heat of the central engine, its temperature drops and excess heat is funneled out by fin-like vents attached to the tops or sides. Stacked-plate designs, by contrast, force oil through a series of metal plates. Heat dissipates as air moves across the plates, and the oil cools faster when it has greater surface area and is shallower, too.

Plated models are often slightly less effective at cooling oil than their tube and fin counterparts since they’re more passive, basically waiting for cooling to happen on its own. A lot of this depends on the application, though. In some settings, stacked plate coolers make more sense.