What is the Difference Between 5w20 and 5w30 Oil? Expert Answer

If you buy something through a link in our posts, we may get a small share of the sale.

5w20 and 5w30 oils are types of oil which have differences in their rate of viscosity. The rate of viscosity of a liquid describes its thickness and stickiness and, therefore, talks about the property of that liquid to flow easily.

When the number is higher (an example of this here is the number 30), then the oil will have more viscosity, and so, have more property of thickness and heaviness and a little ability to flow.

When the number is lesser (an example of this here is the number 20), then the oil will have a lesser viscosity than the one with the higher number, and therefore, have a lesser property of thickness and heaviness and more aptitude to flow.

Oils are essential for vehicles and are the reason to be conscious of these codes and numbers.

Even in such cases when you give your cars to mechanics to change the oil for you, you will do well if you know about the properties of these oil types.

After all, oils are the lifeblood for the engine of your vehicle.

In drawing the difference between 5w20 and 5w30 oil, an example to employ is water. You would notice that water flows very smoothly, and so water will be said to have a viscosity which is very low.

This will help you in understanding this concept. Consequently, the concept of viscosity in the types of oils is critical in determining the long-lasting of your engine and your vehicle.

Understanding the Concept of the Codes

The “W” in the 5w20 and 5w30 oils types stands for “winter.” The number before W which is 5 in these cases represents the rating of the viscosity of the oil in cold weather temperature or conditions of coldness.A man changing the oil of a car

The number which comes after W, such as 20 or 30 in these cases, stands for the weight of the particular type of the oil when it warms up inside the engine of a vehicle.

To analyze the difference between 5w20 and 5w30 oil using the codes, varying weather conditions would come into play. When in winter, for example, the type of oil viscosity that would be advisable to choose would be one which is thin.

With this, the lubrication of the parts of the engine would be smoother unlike when the oil has a higher viscosity. Likewise, when the temperature is higher or at least average, the viscosity of the oil chosen would be one which is higher. So the lubrication would flow in line with the high-temperature rate.

5w oils are multi-weighted. This is unlike the 5-only oils which are single weighted. The difference is that the multi-weight oils will be thicker and useful at normal temperatures than the single weighted oils.

The single weight oils would be thin and as such, protection of the engine of your vehicle would be a little lesser.

5w20 vs 5w30 Oil: Head to Head Comparison

Now, when it comes to picking up your engine oil, you will have to choose one depending on the season or temperature simply. This means you will use a different oil in Winter than what you will use in Summer.

Cold Temperatures

In cold temperatures, 5w20 oil will be the better choice to go for with its thin nature and its ability to bring about less friction due to its viscosity level.

The 5w20 oil type will flow more smoothly than the 5w30 oil. This ability to flow easily confers on it the best choice in cold temperatures. It is because there will be minor heat and the thin nature will still accommodate the oil to flow in-between engine parts and cause lesser friction.

5w30 oil, on the other hand, is thicker and will flow lower than the 5w20 oil. This makes it unideal for cold temperature. Although it has the same rating of 5 in regards to winter, the oil nevertheless weights 30.

So, when there is no much heat, the higher weight rating would not be functional and may hurt the car’s engine. However, you may consider engine block heaters to maximize the oil.

Hot Temperature

In a climate which is hot, the 5w30 oil type would be appropriate for use. This oil type would not break down easily and take longer to break down due to the combination of chemicals that it is composed of.

5w30 oil will form much resistance to heat, and so, when there is much heat, it will last longer in engines and not break down easily.

5w20 oil, meanwhile, would not be appropriate for hotter temperature. This is because this oil tends to break down quickly and has a low viscosity which makes it thinner.

It cannot withstand much heat, and it will quickly create friction between two engine parts. This type of oil would undergo heating up more rapidly than the 5w30 oil and may result of a possible oil leak.A man pouring oil unto the car

How Will You Choose The Appropriate Oil Type?

To know which oil type to choose, you should consider two things:

  • The temperature level of your environment
  • The description in the manual of your car for your car’s engine

Although, it might be sometimes safe to use the 5w30 engine oil type as this will generally be useful for your vehicle when you face a problem in deciding which to use.

However, the best is to know the appropriate type of oil to choose according to the two criteria given, since engines may have varying properties. This way, you will be protecting the life of the engine of your vehicle.

When you check the manual of your car, you would be provided with the type of engine oil to choose. Many a time, each vehicle is specifically built to use a particular type of engine oil.

This would extensively go to say that it is good to know the specific type of oil to use as using one which is against the manual description can hamper the long-lasting of your vehicle.

At other times, you would be good to take into consideration the temperature and climate of your surroundings. In colder temperatures, the best type of oil to go for is the 5w20 oil type because of its thin nature and low viscosity.

In hotter temperatures, however, the best oil type is the 5w30 oil which breaks down less easily and has a higher viscosity. So, you can use the criteria given above to determine the best type of oil for your vehicle.

Things That Can Happen If You Use 5w30 Instead of 5w20

Some engines can safely use both types of oil. So if you are out of options, you may be able to use 5w30 instead of 5w20. Make sure you check your owner’s manual since it will tell you if your engine is good for both types of oil. 

If you happen to use 5w30 instead of 5w20 when your engine is not compatible, you may end up risking your engine. The engine’s components may not operate smoothly and seamlessly as before. 

The oil you used is thicker and it forces the engine’s component to work extra hard than usual. Overworking your engine’s components could result in damages that might be irreparable. 

Things that Can Happen If You Use the Wrong Kind of Oil in Your Car

These are some of the consequences that can happen when you use the wrong kind of oil in your car. People often get careless and use the wrong oil for their engines without knowing it. 

Knowing the effects when you’ve used the wrong oil could prevent any further damage to the engine or accidents. 

Unusual Engine Noises

Your engine may make louder sounds than you’re used to hearing. Engines will usually produce ticking or knocking sounds when they used the wrong type of oil. If you have great hearing, you will notice it easily. 

Your engine will make these noises because the parts of your engine are working harder than normal. 

Oil Leaks 

When the oil you used is too thick or too thin for your engine, it may lead to leakage. The leak can come from different valves, gaskets, and other engine components. 

This is harder to spot usually since leakage is minimal at first. The best way to spot them is when your car is stationary. So better check if there are few drops of oil in your garage or driveway. 

Burning Smell Around Your Car

The wrong type of oil won’t be able to lubricate all the components of your engine properly. In turn, it will lessen the lubrication which in turn increases the friction. Friction creates heat that you can smell. 

The oil used cannot handle the lubrication of the entire engine. While it thins out, it gets subjected to friction that generates heat. This burns up the oil creating that distinct burning smell. 

If you notice the burning smell or smoke coming from your engine, stop your vehicle at once. Make sure you are parked in a safe place. Call a mechanic to get your engine checked and fixed. 

You’ll Need Fuel More Often

Since your engines are working harder than usual, it is natural that they will consume fuel at a faster rate. This is harder to notice if you don’t check your daily or weekly fuel consumption. 

However, it should be noticeable when you use the car for longer periods of time. You will start to notice you’ve been needing to fuel up more often even when driving your usual route. 

Mixing 5w20 and 5230 Oil

There are instances where you can mix both 5w20 and 5w30 motor oil if your engine can accommodate both. As mentioned before, you can check if your engine allows both 5w30 and 5w20. If it does, you can mix both oil and use them on your engine with no problems.

However, you should also be aware that you could void your warranty. If you used the wrong type of oil in your engine while it’s still under warranty, you may null your warranty. Hence, it’s always important to read your owner’s manual before tinkering with your car’s engine. 

Also, be aware that you may also weaken the engine components’ durability. Some people have tried mixing both oil and used it on engines without problems. However, it also leads to faster wear and tears to the components. A rack full of engine oils

What to Do if You Use the Wrong Kind of Oil 

Don’t panic. It’s not the end of your engine if you put the wrong oil in it. Most damages to your engine won’t be significant (if you are able to spot it fast). Most people often find something is wrong in their next oil change. 

Go get your car an oil change and make sure you use the right oil this time around. Damages to your car due to wrong oil isn’t significantly noticeable for the first few days and even weeks. 

So it’s important that you are able to spot any unusual things about your engine. What can really damage your engine, is the consistent use of the wrong oil. This can happen if you don’t do regular maintenance. 

Frequently Asked Questions (FAQs)

1. Why Should I Use the Right Oil and Not Just Any?

For longer engine life, less non-routine maintenance and for better mileage, it is required that you use the right oil designed for your engine.

2. Between 5w20 and 5w30 Which One Is Economy Friendly?

Many experts recommend 5w20 to 5w30 when it comes to economy friendliness. It causes less friction in the engine as it is very thin.

3. Why Are Cars Designed With Engines Supporting Different Oil Weights?

The cars are designed to serve different purposes and to be used in different environments. The various engines supporting different oil weight make them suitable for different situations.

4. Is It Applicable to Interchange Between 5w20 and 5w30?

No. If your manufacturer has recommended one type of oil, you should stick with it. This is because engines are designed to run on specific types of oil which comes with different viscosity.

5. What Is the Difference Between Single and Multi-Grade Oil?

Single grade oil is a pure type of oil that cannot be modified. It has no additives while the multi-grade oil has additives thus not pure.


The two types of oil, 5w20, and 5w30 have been a point of discussion for so long. Many people have been found themselves confused to choose 5w20 vs 5w30 two types of oil. Have you been among them?

This article has laid down the differences to make your choice stress-free and straightforward.