Four Telltale Signs of a Bad Oil Cooler

No matter what type of car or truck you drive, the cooling system is critical to the engine running smoothly. While chances are good that you won’t think much about your vehicle’s cooling system over the life of your car, there is an equally good chance that it will wear out at some point.

Chevrolet/GMC Automatic Transmission Oil Cooler fits 2003-2009 C4500 Kodiak, C4500 Topkick, etc. Photo MainAn engine oil cooler allows the engine’s cooling system to remove excess heat from the oil. In most cases, oil coolers are water-to-oil heat exchangers. This means that engine oil goes to the oil coolers through an adaptor located between the engine block and the engine oil filter. Oil then flows through cooler tubes while engine coolant surrounds those tubes. The heat from the oil is transferred through the walls of the tubes to the surrounding coolant. Finally, the heat that is absorbed by the cooling system is transferred to the air as it goes through the radiator.

The key to keeping your oil cooler in good working order is to make sure you change your oil and filters regularly. Even so, routine maintenance is not always enough to prevent wear and tear on an oil cooler. If your vehicle’s oil filter needs to be repaired or replaced, there are four telltale signs.

  1. Oil leaks. Oil leaking under your engine is always an issue that should be brought to the attention of a mechanic who can determine where the leak originated. The adaptor within the oil cooler has an gasket or rubber O-ring that could have failed, causing an oil leak.
  2. Engine coolant leaks. When coolant is leaking, the engine will eventually overheat. A very small leak will lead to coolant on the ground under the vehicle while a large leak may lead to steam coming out from under the hood.
  3. Oil in the cooling system. If the adaptor of the oil cooler breaks down, you may see engine oil in the cooling system. This occurs because when the engine is running the oil pressure will be greater than the pressure in the cooling system and oil will be forced into it.
  4. Coolant in the oil. If your vehicle’s engine is not running and the cooling system is pressurized, this can force coolant into the oil pan, leading to engine damage.

In some cases, flushing the cooling system and engine will be all that is required. If the oil cooler adapter fails, however, it will need to be replaced and the oil cooler may also need to replaced, or at the very least, flushed.

Ace Radiator carries only the finest quality cooling products on the market. Our HD truck radiators and cores have been road tested to hold up under the most stressful conditions. Ace Radiator backs their radiators with a one year guarantee.

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