Updated at: 06-08-2022 - By: Lucas

It might be difficult to choose the best engine oil for your vehicle because there are so many possibilities. Motor oil 15w50 vs. 20w50 will be compared in the next article.

Consider the following factors while selecting an oil:

  • Protects against natural wear to a high degree;
  • During operation, the engine elements with the most intensive grinding are protected by a thick oil layer;
  • Due to high-quality heat dissipation, the device is protected against overheating;
  • By eliminating leaks, fuel consumption is reduced.

15w50 engine oil

15w50 engine oil

This type of oil is commonly used in sports cars because it provides a thicker oil coating, which reduces wear on motor components.

This type of oil is designed to give maximum lubrication for engines operating in harsh circumstances. Towing or racing vehicles might also benefit from this product, as it can withstand high temperatures.


15w50 engine oil has a viscosity index of 152. As a result, the oil’s viscosity or thickness will not change significantly under a wide variety of temperatures. So it’s a great option for vehicles that are used in a wide range of environments.

Temperature range

A 15w50 engine oil has a temperature range of 5°F to 104°F, or 40°C to +40°C. Because it can be used in both hot and cold regions, it is an excellent choice for cars.

This prevents the buildup of unpleasant deposits, ensuring that your engine will last longer. It’s a fantastic choice for engines that run in harsh conditions because it helps prevent wear and tear.

As a result of its increased viscosity, it can withstand a wider range of temperature changes.

API rating

SJ is the API designation for 15w50 motor oil. American Petroleum Institute (API) certification signifies that the oil has been thoroughly examined and authorized. It’s a terrific fit for cars in the North American market.

ACEA properties

A0, A01, A02, and B0 are the ACEA qualities of 15w50 engine oil. The European Automobile Manufacturers Association has tested and approved this oil.

ILSAC rating

The International Lubricants Standardization and Approval Committee has tested and approved the ILSAC GF 0, GF A, and GF B ratings for 15w50 engine oil.

20w50 engine oil

20w50 engine oil

Motorcycles, vintage automobiles, and heavy machinery can all benefit from a 20w50 oil (agricultural equipment, special vehicles, etc. ). They are exposed to a greater load during the summer months.

The highest temperature at which the liquid preserves its properties and performs its protective function with high quality is defined as 20W.

The SAE classification states that the oil is suitable for use down to 15 degrees Celsius. At 40°C and 100°C, the oil’s kinematic viscosity is limited to 50. Oil thickens as this number rises.


20w50 engine oil has a viscosity index of 142. Because of this, it is a fantastic choice for vehicles that operate in a wide range of weather conditions. Oil will thin less in hot weather and thicken more in cold weather when its viscosity index is higher.

Temperature range

4°F to +104°F or 20°C to +40°C is the temperature range for 20w50 engine oil. Because of this, it is a fantastic choice for vehicles that operate in a wide range of weather conditions. When it’s hot or cold, you can count on it to keep you safe.


SN is the API designation for 20w50 engine oil. A service level designation signifies that the oil meets all specifications set forth by the American Petroleum Institute (API).

ACEA properties

A0, A01, and A02 are the ACEA characteristics of 20w50 engine oil. As a result, this implies that the oil meets all of the conditions set forth by this association.

Now, let’s take a look at the distinctions between these two types of oil to see what we can learn.

Difference between 15w50 and 20w50 engine oils


The viscosity of 15W50 and 20W50 engine oils is the most significant distinction. Flowability is influenced by the viscosity of the oil; this is a measure of how thick or thin a liquid is. With regard to heat, thinner oils are more vulnerable and more vulnerable to heat breakdown, whereas thicker oils are more resistant.

As a result, 15W50 oil resists heat buildup more effectively than 20W50 oil. However, because it is thicker and more viscous, it can be more difficult to move when it is cold.

In cold weather, 20W50 oil flows more easily than 15W50 oil because it is thinner and less viscous. However, 20W50 oil is more susceptible to heat buildup.

When to use 15w50 engine oil?

An engine oil that is 15W50 is a suitable choice for hot climates or if you frequently drive in stop-and-go traffic. Your engine will run more smoothly because of the reduced risk of overheating.

When is it best to use 20w50?

It’s recommended to use 20W50 engine oil if you reside in a cold area or frequently travel long distances in your car. Keeps the engine warm and prevents freezing.

Motorcycles use 20W50 more frequently than vehicles.

How does using 15w50 oil affect the engine?

Most engines benefit from using 15W50 oil because it minimizes the amount of heat that builds up in the engine. Fuel efficiency and pollution can also be improved by using this device.

When not changed in a timely manner, 15w50 oils can have detrimental effects on the engine, such as wear and tear on engine parts.

How does 20w50 affect the engine?

However, compared to 15W50 oil, using 20W50 oil can help your engine last a little longer. It has a lower viscosity index (VI) than 15W50 oil, so it flows more freely when temperatures drop. However, this could make it more prone to malfunctions caused by excessive heat.

15w50 engine oil fuel consumption

Between 15W50 and 20W50 engine oils, there isn’t much of a difference in fuel usage. Even yet, using a richer oil, such as 15w50, can improve fuel economy slightly.

20w50 fuel consumption

Between 15W50 and 20W50 engine oils, there is no substantial variation in fuel usage. However, using a thinner oil such as 20w50 can reduce fuel economy by a small amount.

Which type of engine oil is better for my car?

In the end, what type of engine oil you should use depends on your driving habits and the weather conditions where you live. 15W50 engine oil is a suitable choice if you live in a hot area or drive in heavy traffic.

If you have a motorcycle or a large vehicle, 20W50 oil is a better option for you. Consult your car’s owner’s manual or a professional mechanic if you’re unsure about what sort of oil to use.

Benefits of using 15w50 engine oil?

To reduce heat buildup, improve fuel efficiency and reduce pollutants, 15W50 engine oil can be beneficial. It’s safe for most engines and can help you get more mileage out of your ride.

Disadvantages of using 15w50 engine oil

Heat-related breakdowns are more likely to occur.

Benefits of 20w50 oil

In addition to decreasing heat buildup, 20W50 engine oil improves fuel economy and reduces pollutants.

For most engines, it’s a good idea to use this product. However, there are also drawbacks, such as higher engine part wear and tear.

Disadvantages of using 20w50 engine oil

  • Less viscous than 15W50 oil, which can make it flow better in cold weather but also means it’s more likely to shear down at high temperatures
  • More prone to engine wear and tear.

How often should I change the engine oil?

According to most automotive experts, you should change your engine oil every six months or one year, whichever comes first. Depending on your driving habits and the type of oil you use, you may need to change your engine oil more frequently than the manufacturer recommends. Ask a professional or check your owner’s handbook for further information.


Which engine oil works best for your car is ultimately a personal choice. 15W50 and 20W50 both have their advantages and disadvantages, so choose the one that most suits your needs.

If you’re unsure about the proper weight of oil to use, talk to a professional before making any changes to your vehicle.