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What Is the Optimum Engine Oil Temperature? (Explained)

To keep running your engine smoothly, the oil temperature plays a great role. High oil temperature is good for the engine but not much warmer than the coolant temperature. If the oil temperature rises too high, it can cause serious problems.

What is the optimum engine oil temperature?

The optimum operating engine temperature is considered in a range of 195 to 220 degrees Fahrenheit. If the temperature exceeds 230 F, the engine becomes overheated. Above 245 F, it can result in a thermal breakdown. However, some conventional motor oil can hold temperature up to 250-270 F.

For a smooth engine, it requires high oil temperature but only a few degrees warmer than the coolant temperature. If the engine oil temperature goes really high, it can cause great damage. The optimum engine oil temperature is 195 to 220 degrees Fahrenheit. 

Synthetic engine oil:

Synthetic engine oil is great for handling higher operating temperatures. The optimum temperature of synthetic engine oil is 300 to 320 degrees Fahrenheit. Without burning or breaking down, it can also safely hold up to 450 degrees Fahrenheit. 

Synthetic engine oil has lower oil consumption and also has better engine protection. It’s well suited for overhead camshaft engines,  turbocharged, heavy-duty and hard to use applications. 

It doesn’t break down as easily as the ordinary mineral based oils as it has a high temperature tolerance capacity.

Diesel engine oil:

Diesel engine oil has lower temperature pumpability and also has higher viscosity. The optimum temperature of diesel engine oil is 210 to 230 degrees Fahrenheit. However, it can hold up to 240 to 250 degrees Fahrenheit.

The temperature of the diesel engine passes directly through the oil cooler. The diesel oil cooler has a bypass valve that works for the flow of oil preventing blockages. 

But the valve is so sensitive that it can’t hold excessive pressure and temperature. That’s why it can’t hold that much higher temperature like synthetic engine oil.

What temperature is too hot for engine oil?

The optimum engine oil temperature is 195 to 220 degrees Fahrenheit. Temperature up to 230 is acceptable. But above 230 degrees Fahrenheit is too hot for engine oil. Temperature above 245 degree Fahrenheit can cause serious damage to the car. 

If you are willing to run your engine smoothly, you should be careful to keep the temperature stable and below a certain level of heat. It’s wise to maintain your needle in the middle of your gauge to avoid serious damage.

If the temperature rises up to 230 degrees Fahrenheit, the water gets mixed up with sulfur and creates acids that can cause a chemical reaction in the motor oil. 

It will change oil’s viscosity and the motor oil will degrade. Even if the temperature rises above 245 degrees Fahrenheit, it can cause thermal breakdown and damage chemical bearings. 

Why is my engine oil temperature high? What does it mean when your engine oil temp is high? 

Engine oil temperature rises up for any malfunction of the oil pressure sending unit. If your engine oil temperature is high it does mean: 

Blockage in the cooling system:

There might be something obstructing in the cooling system that’s hampering coolant circulation. The coolant doesn’t flow properly and as a result, the radiator won’t be able to diffuse the heat. 

There must be anything between the grill and the radiator or the condenser that has blocked the area and hampering the coolant system.

Damaged water pump:

Damaged water pump doesn’t let water to circulate and avert the cooling system. It stops turning and flows out the heat. As a result, the heat gets stuck in the car and causes overheating. 

Valve malfunction:

Valve provides a place for the oil to flow when the engine oil pressure gets too high. 

The valves allow oil when the pressure level goes a certain level. The oil pressure and the temperature quickly go really high if there’s any malfunction in the valve which isn’t safe for the engine.

Thinner oil and viscosity:

The grade of viscosity to a thicker or thinner oil has a great effect on the oil temperature and pressure. If the engine oil is thicker, it cools down but when the oil is thinner, the engine oil heats up. 

How to keep engine oil temperature down? 

Here are the ideas to keep engine oil temperature down:

Use the right coolant and the radiator:

To keep your engine cool you must use the right coolant and a radiator. If there’s any damage to the coolant the cooling circulation will hamper and the radiator won’t work properly.  

If the radiator has water in it, you’ve to change it immediately. Using the right coolant and radiator will eventually help to keep engine oil temperature down.

Use a clip-on deep-fry thermometer:

It’ll be wise to use a clip-on deep-fry thermometer to maintain proper oil temperature. Just you’ve to keep a close watch. If you notice, the oil has become slightly smoking, it means the engine oil is overheated. 

Only you have to remove the pot from heat and it’ll result in the engine oil temperature down. 

Pay attention to engine maintenance:

Engine maintenance has significant impacts on the performance of the vehicle and as a result, you can keep engine oil temperature down. 

You must keep the air filter clean and the tire pressure should be at the correct level. You can unpack your trunk as well to place less strain on the engine. 

Final Thoughts

It’s considered that the optimum engine oil temperature is in the range of 195 to 220 degrees Fahrenheit. Temperature above 230 F causes overheating and above 230 F it can cause great damage to the car. But the synthetic engine oil has a higher temperature holding capacity than diesel engine oil.