0w20 vs 5w20 Oil

A vehicle’s engine oil keeps its components lubricated and prevents corrosion. It keeps the heat buildup in check to prevent overheating of the engine. Engine oils come in different types- synthetic and mineral, single and multi-grade, seasonal (summer and winter-grade), etc.

0w20 and 5w20 are two popular winter-grade oils in the market. These are the most preferred choices for gasoline and diesel vehicles. But what exactly are 0w20 and 5w20 engine oils? What is the difference between the two? How do you make out which oil to use for your vehicle? Why do people choose 0w20 oil for extremely cold conditions?

Let’s read and find out the answers to the above questions and many more.

What is Oil Viscosity?

Viscosity is the resistance of a liquid to continue to flow at a given temperature. Generally speaking, thin oils flow better in colder conditions or lower temperatures than thick oils. That means thin oils have a higher viscosity than thicker oils. Such oils are marked as winter-grade due to their ability to retain the liquid state even in freezing temperatures.

Thick oils are marked summer-grade as they can retain the film strength and oil pressure even when the temperatures soar.

How can we determine the viscosity of engine oils just by looking at the container or name? The Society of Automotive Engineers (SAE) came up with a numerical coding system in 1911 for grading oils based on their viscosity. The code was initially mono (single) grade but gradually became multi-grade when oil manufacturers began to add additives to alter oil viscosity.

The current coding system is XW-XX. Here,

The single-grade oils are represented as XW, where X is cold/ hot operating viscosity, and W is winter. There are eleven single-grade oils with 0W, 5W, 10W, 15W, 20W, & 25W used for winter-grade oils and 20, 30, 40, 50 & 60 used for summer-grade oils. Single-grade oils cannot be altered with viscosity modifiers.

Multi-grade oils contain additives/ polymers that make them suitable for a range of temperatures. Hence, the viscosity grading will show both ends of the temperatures (the lowest and highest) that the oil can handle.

0W20 and 5w20 are both multi-grade oils as they have the properties of winter-grade and summer-grade oils.

But, how do the two oils differ? Do the oils have any similarities?

0w20 vs. 5w20 Oil: The Key Differences

0w20 and 5w20 are synthetic multi-grade oils suitable for cold and hot temperatures.

Hot Viscosity

Hot viscosity is the extent to which the oils can sustain in hotter temperatures. Both 0w20 and 5w20 have the same hot viscosity of SAE 20 weight oil. This translates to a maximum temperature of 68°F. The oils will not burn in excessive heat conditions. The oil consumption will also be balanced (though this depends on the engine).

Cold Viscosity

Cold viscosity is the thickness of oils in colder/ lower temperatures. While 0w20 has a cold viscosity of SAE 0W weight oil, 5w20 has a cold viscosity of SAE 5W weight oil. The lower the value before W, the better will be its viscosity in colder climates. That makes 0w20 a better choice for very cold temperatures than 5w20.

5w20 is also winter-grade oil but works the best in temperatures ranging between -22°F and 68°F. 0w20 is suitable for temperatures as low as -35°F. It will continue to be in this thin liquid form and provide the necessary lubrication to the engine’s parts.

Fuel Economy

0w20 and 5w20 have similar fuel economy and mileage. 0w20 might be marginally better as it is thinner and easier to flow. That said, it would depend on which type of 0w20 engine oil you choose. Fully synthetic 0w20 gives the best fuel economy to vehicle owners.

Similarly, fully synthetic 5w20 also has great fuel efficiency. In fact, 5w20 is a globally preferred engine oil that can be used in fair weather conditions. The manufacturers from the US, Europe, and Japan choose 5w20 engine oil.


We already know that 0w20 and 5w20 are good performers at lower temperatures. However, 0w20 is the best choice for cold starts. If you want to start your vehicle’s engine in freezing temperatures, you need 0w20 oil. It prevents engine wear and sustains oil pressure. It also prevents sludge buildup due to cold conditions.

If you want a smoother engine in seasonal conditions (varying between hot and cold), you have to choose 5w20 oil. It is slightly thicker and can handle hot temperatures by maintaining its viscosity (and becoming too thin). Fortunately, some vehicles are compatible with both types of oils. You can use either depending on where you live.


The pricing varies on the brand (seller) and the type of oil (full or semi-synthetic). That said, 0w20 is a bit more expensive than 5w20 because it has better viscosity in colder temperatures and is more stable in freezing conditions. Both oils are costlier compared to single-grade engine oils.

Factors to Consider When Choosing Between 0w20 and 5w20 Oils

Though you should follow the manufacturer’s instructions, sometimes, you have the option of using either engine oil. Choosing between 0w20 and 5w20 oil requires consideration of the following factors.

Frequently Asked Questions

Can 0w20 be used instead of 5w20 or vice versa?

You can use 0w20 oil instead of 5w20 or vice versa if the manual recommends both oils for the vehicle. Otherwise, it is better not to substitute one for another, especially if you live in colder climates.

Though both have similar viscosity, they are not the same. Substituting one with the other can lead to engine damage in the long term. However, you can use them in emergencies (make sure to drain the oil and refill the oil tank with the recommended one once you are out of the emergency conditions).

Why is 5w20 good to use in cold regions?

5w20 is winter-grade oil because of its cold viscosity number. Though it is not as thin as 0w20 oil, it is still useful in temperatures as low as -22° F. The oil will retain its liquid state and maintain the necessary pressure to keep the engine running properly.

How frequently should you change 0w20 oil in your vehicle?

Regularly changing engine oil will increase the lifespan of the engine and prevent the components from wearing out faster. The manufacturer will mention the frequency of oil changes in the vehicle’s manual. Typically, you should change your 0w20 engine oil once after every 8000 or 10,000 miles. Depending on the vehicle’s performance, you can extend it to 15,000 miles.

Are 0w20 and 5w20 synthetic oils?

Well, 0w20 is either semi-synthetic or fully synthetic. Polymers and additives are a must to ensure that the engine oil maintains the necessary viscosity to stay thin in freezing conditions. Synthetic oils are more stable and robust. 5w20 is available as conventional and synthetic oil. Conventional 5w20 is suited for hotter temperatures as it is made from crude oil. Synthetic 5w20 is better for colder temperatures due to its stability.

Using 0w20 oil when not recommended will lead to engine wear and tear. It is not suitable for engines that operate in higher temperatures like the ones in aircraft or two-wheelers.

What will happen if you mix 0w20 and 5w20 oils in your vehicle?

We don’t recommend mixing two or more types of oils, even if they are similar. 0w20 is synthetic oil, whereas 5w20 can be synthetic or conventional. Even if it is synthetic, mixing 0w20 with 5w20 will reduce fuel economy and cause engine problems over time.

Final Words

0w20 and 5w20 are popular engine oils known for their viscosity and multi-grade rating. While 0w20 is used in smaller cars, 5w320 is used in SUVs with diesel and light petrol engines.

However, follow the manufacturer’s recommendations about which engine oil to use in your car. Ask the dealer to recommend the best brand of engine oil and ways to take good care of the vehicle to increase its longevity.