0W20 Vs 5W20: Which Is The Best Oil?

0W20 vs 5W20 both are thin engine oil and are recommended for cold environments but whose the best? This depends a lot on what you want and what factors you consider before selecting the engine oil. Factors like cold viscosity, hot viscosity, performance, useful life, and price influence a lot of engine oil selection.

A vehicle engine is a complex assembly of a lot of metal parts and mechanical mechanisms that work together to make a vehicle more. As engine parts are made of metal and there is very high friction where there are two metal parts sliding over each other.

To make things worse high heat and pressure make metal wear faster. To prevent metal wear, reduce friction and make the engine work properly, a highly qualified and properly selected engine oil is needed.

5W20 vs 0W20 are the two most popular engine oil in the automotive sector and work best to protect engine components. Now the question is from 0W20 vs 5W20 which is the best oil for your vehicle?

Well, that depends on a lot of factors like cold viscosity, hot viscosity, performance, useful life, and price. This article is all about comparing and finding the best oil between 0W20 and 5W20.

0W20 Vs 5W20

Comparison Of The 0W20 Vs 5W20 Oils!

Both when it’s about the argument of 0w20 oil vs 5w20, these oils are recommended for low-temperature cold climates and work best under extreme conditions. Both perform well under normal temperature conditions but one of the 0w20 offers better protection at low temperatures.

You should know the detailed difference between 0w-20 and 5w-20. For this, comparing the following factors will help.

  1. Cold Viscosity
  2. Hot Viscosity
  3. Performance
  4. Price
  5. Useful Life

Cold Viscosity

Viscosity is the measure of resistance fluid during its flow. The higher the viscosity poor will the be the oil performance for reducing friction. Cold viscosity is viscosity in extremely low temperatures and for good engine oil lower the cold viscosity better it is.

In ‘0w 20 vs 5w 20’ both 0W20 and 5W20 numbers before W that is 0 or 5 define the cold viscosity of engine oil. As per procedure, the lower the number before W lower will be the cold viscosity of the engine oil.

So, in the 0w-20 vs 5w-20 battle, 0W20 is better than 5W20 in terms of cold viscosity and therefore highly recommended for cold weather.

Hot Viscosity

As explained above about viscosity and cold viscosity, Hot viscosity is the viscosity of the oil at high temperature. A good engine oil should maintain its viscosity at elevated temperatures and not heat up quickly.

In this regard numbers after W represent oil’s ability to resist heat and define its viscosity at elevated temperatures. As both have 20 after W so their performance at elevated temperatures will be the same. So, yes, when it’s about the 5w-20 vs 0w-20 fight, both get the same score in terms of hot viscosity.


Regarding the performance of ow20 vs 5w20 oil, both are thin engine oils and perform quite well under cold environments. 0W20 being thinner than 5W20 work better with cold starts and prevent problems like varnish deposit, engine wear and low oil pressure.

5W20 also work well in cold climate but work better in a seasonal climate. With its slighter thicker viscosity, it cleans and lubricates the engine quite well. It can handle high temperatures a bit better than the other one.

If you ask for the best 0w20 oil, Castrol Edge, Liquimoly Motor Oil, and Pennzoil Oil are some of the best options. 

Price Point

If mentioning the 0W20 vs 5W20 price, they noticeably differ if you analyze the recent stats. To make it clear, the 0W20 oil comes at $30 – $200 based on the quality.

Some oil comes at less than $30 like the Castrol 03124 Edge even being a top-notch item. On the contrary, the 5W20 oil started in the $20 – $170 price range.

Useful life

As for the useful life of 0w20 vs 5w20 oil, the 0W20 oil will last not more than 5,000 – 10,000 miles. In other words, using this kind of oil will help your engine stay operating for 6 – 12 months.

Then again, the 5W20 oil will last for around 10,000 – 20,000 miles between the oil change. Meaning that it will keep the engine lubricated for 1 year.

Can You Use 5w20 Instead Of 0w20?

You can not use 5w20 instead of 0w20 in extremely cold weather or your car engine can encounter start-up difficulties. However, in normal climatic conditions, it’s okay to use 5w20 instead of 0w20.

People have confusion like ‘Is 0w20 thicker than 5w20?’ The answer is no. 0W20 is thinner compared to 5w20 oil.

Since the 0w20 oil is thinner and has a lower viscosity, it flows more readily at cold temperatures and provides better lubrication along with better protection.

But it doesn’t matter in normal driving conditions. The 5w20 oil doesn’t flow to the top at only cold temperatures due to its higher viscosity and thickness. Otherwise, both oil works quite the same. So, in such cases, using 5w20 instead of 0w20 is okay.

Now, if you ask ‘Can I use 0w20 instead of 5w20?’

You can use 0w20 instead of 5w20 as it always offers great flow. But make sure you check the owner’s manual to see if it’s recommended. Because your car runs at its best and longest when you follow what’s recommended.

What Happens When You Use 5w20 Instead of 0W20?

We’ve already cleared a question ‘can you run 5w20 instead of 0w20?’ This time, we’ll share the consequences of using the thicker 5w20 oil as an alternative to 0w20.

  • Difficulty during start-up: Since the 5w20 oil is already thicker than 0w20, the thickness increases at cold temperatures. So, this oil can’t flow as easily as 0w20 and it doesn’t provide the same protection as well. It may result in increased wear and tear and you may experience a critical start-up period.
  • The risk of engine damage: When you interchange the oil during cold weather, the wrong viscosity may cause engine damage and decreased engine performance.
  • Reduced fuel efficiency: Since thicker oil is responsible for increasing engine friction, it will eventually reduce fuel efficiency.

Some of the best 5w20 oil options are the Mobil 1, Pennzoil 5w20 oil, and Royal Purple 5w20 oil.

Can You Mix 5w20 and 0w20?

Although it’s possible to mix 5w20 and 0w20 oil together, you should not do it, especially in cold weather temperatures. It’s because the 0w20 oil is too thin to perfectly blend with the 5w20 oil.

Plus, the 0w20 oil is fully synthetic whereas 5w20 can be either fully or partially synthetic. Since they’re different in formulation and viscosity, it’s best not to mix them.

But both oils work almost the same when used in moderate temperatures. For this, some people support mixing the oils. Still, you know the difference that 0w20 oil offers better protection in cold weather and 5w20 offers better protection in warm conditions.

So, you must be very careful about the weather conditions even if you don’t have any choice but to mix them.

Also, there’s a bigger concern regarding mixing the oils together if your vehicle is still under warranty. Mixing 0w20 oil with 5w20 oil may cause your car’s warranty to be voided.

Can You Put 0w20 In A 5w20 Engine?

Although it’s possible to put 0w20 oil in an engine that has 5w20 oil, it’s not recommended. If you have no choice other than that, make sure you have already drained the existing oil before putting 0w20 in a 5w20 engine.

Otherwise, adding 0w20 oil to the 5w20 when the latter one is still a lot will result in an improper blending of the oils. Topping one type of oil to another will not let them blend well.

Also, both 0w20 and 5w20 oil have different additives to break contaminants in your engine. When you mix them together, the combination of those additives will not be good for the engine.

Engine oil 0w20 vs 5w20

Last Words

Finally, the 0w20 vs 5w20 debate is over after hinting at their differences. Depending on the engine and performance requirement, you can select one easily.

I would pick the 5W20 if price, longevity, fuel economy, and engine protection are what matters most when looking for motor oil.

But then again, I would go with 0W20 instead of 5W20 if my priorities are viscosity, lubrication, and better flowing at cold temperatures.  

Hope this guide was able to give plenty of information that you need to know for making a choice between both of these oils. See You Soon!

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William Baldwin

This Is William Baldwin, The Founder & Managing Editor of this website. Me and my team share automotive tips, tricks, and news

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Talha Atta

Talha Atta, a Mechanical Engineer and experienced technical content writer and editor at Autoglobes.com with a passion for the automotive industry.