0W20 vs 5W20 Oil: Which is better? (Difference and Similarities)
Winter-grade oils like 0W20 and 5W20 are made for cold weather. They let your engine work at optimal levels and share a lot of similarities. So, what’s different about them? How are SAE 0W20 and 5W20 motor oils different?
Apart from their composition and the temperature at which they flow, both oils are very similar. While they are both low-temperature motor oils, 0W20 is arguably better in extremely cold temperatures.
This post will describe the viscosity grades and advise when each oil type should be used. You’ll also learn about different motor oil mixtures and get answers to frequently asked questions. Continue reading to learn how to tell the difference between 0W20 and 5W20.
Contents
Oil Viscosity
Oil viscosity is the reluctance of a liquid flow at a given temperature. Thin oils flow more freely at lower temperatures than thicker, higher-viscosity oils.
Thin oils are often winter-grade because they minimize engine friction and allow the engine to start quicker in cold weather. Thick oils, often known as summer-grade oils, have higher film strength and oil pressure at high temperature, and when the vehicle is hauling or carrying heavy objects.
The Society of Automotive Engineers (SAE), devised a numerical code system for rating oils based on their viscosity characteristics in 1911 (SAE J300). Motor oils were initially all mono-grades since oil makers had to start with heavy oil to attain the proper thickness at operating temperatures.
Eventually, additive technology enabled oil to thin more slowly, allowing a choice of thinner oil to decide film thickness. The viscosity categorization format is XW-XX, where X represents the cold operating viscosity, W represents winter, and XX represents the hot operating viscosity of the motor oil.
Single-Grade and Multi-Grade Oil
Viscosity grades come in two types: single-grade and multi-grade. There are 11 viscosity grades for single-grade motor oils: 0W, 5W, 10W, 15W, 20W, and 25W for low-temp grades, and 20, 30, 40, 50, and 60 for high-temp grades. This type of oil can’t be changed in terms of its thickness, so it’s often called a “straight-weight oil.”
Multi-grade motor oils contain unique polymers that enable them to function in a wide temperature range. When cold, they would have the same thickness as the base grade and the second grade. For instance, an SAE 5W20 oil would work like an SAE 20 at 100 °C (212 °F) and an SAE 5 at cold temperature (5W for winter).
Viscosity Grades
Below is a table from Anton Paar that shows the different viscosity grades for both high and low-temperature motor oils. The numbers in italics show changes to the SAE J300 system. Currently, there are 14 different viscosity grades.
| SAE Viscosity Grade[°C] | Min. Viscosity [mm²/s] at 100 °C | Max. Viscosity [mm²/s] at 100 °C | High Shear Rate Viscosity [mPa.s] at 150 °C | Cranking Viscosity
[mPa.s] max. at Temp. [°C] |
Pumping Viscosity [mPa.s] max. at Temp. [°C] |
|
0W |
3.8 |
— |
— |
6,200 at -35°C |
60,000 at -40°C |
| 5W | 3.8 | — | — | 6,600 at -30°C | 60,000 at -35°C |
| 10W | 4.1 | — | — | 7,000 at -25°C | 60,000 at -30°C |
| 15W | 5.6 | — | — | 7,000 at -20°C | 60,000 at -25°C |
| 20W | 5.6 | — | — | 9,500 at -15°C | 60,000 at -20°C |
| 25W | 9.3 | — | — | 13,000 at -10°C | 60,000 at -15°C |
| 8 | 4.0 | <6.1 | 1.7 | ||
| 12 | 5.0 | <7.1 | 2.0 | ||
| 16 | 6.1 | <8.2 | 2.3 | ||
| 20 | 6.9 | <9.3 | 2.6 | — | — |
| 30 | 9.3 | <12.5 | 2.9 | — | — |
| 40 | 12.5 | <16.3 | 3.5 (0W-40, 5W-40 & 10W-40 grades)
3.7 (15W-40, 20W-40, 25W-40 & 40 grades) |
— | — |
| 50 | 16.3 | <21.9 | 3.7 | — | — |
| 60 | 21.9 | <26.1 | 3.7 | — | — |
I’m not going through all the different motor oil grades, so you don’t need to worry about being too overwhelmed with all these numbers. Only the 0W20 and the 5W20 variations will be covered in this article.
0W 20 Oil vs. 5W20: Explanation
In 1952, 0W20 oil was added to the SAE J300 EOVC system as one of the low-temperature grades. It is a liquid that is made to flow smoothly as an SAE 0 in extreme cold weather and an SAE 20 once the engine has reached its full operating temperature.
Even at -35°C/-31°F, this oil will still flow through the engine oil ways. This oil prevents vital engine parts from getting too dry, which makes it easy to start your engine when it’s cold in the winter.
0W20 vs 5W20: Fuel Economy
5W20 is low-temp grade motor oil usually recommended for winter, while 0W20 is a better choice for warmer weather. This type of oil is common because it gets the best gas mileage, uses less gas, and puts out less pollution. Motor governments and manufacturers across the globe want 5W20, especially in Japan, Europe, and the U.S.
0W20 and 5W20 are high-quality synthetic grades oil with low viscosity that can significantly improve fuel economy. When used in normal temperatures, their qualities are the same. Also, when used in cold weather, there isn’t much variation between the two versions.
When to Use 0W20 and 5W20
When determining which of the two oils to use, the factors listed below should be taken into account:
The Owner’s Manual
Check your owner’s manual to see what viscosity of motor oil is recommended for your car. If both 0W20 and 5W20 are on the list, feel free to switch depending on the weather.
Manufacturer Requirements
When your vehicle carries a significant amount of cargo, the machine designer would recommend you use engine oil that has a high viscosity and is thick like honey. On the other hand, if it runs quickly, you should choose a lubricant that can move out of the way and back again in the same amount of time.
Fuel Economy
Despite the fact that both 5W20 and 0W20 (0W20 synthetic oil) can be used at temperatures of 20°C/68°F, 0W20 is thinner than 5W20 when the engine is cold, particularly in the first few minutes after you start your vehicle. New cars need it because, compared to the 5W20, it gives the vehicle a better gas mileage. The 0W20 version is also suitable for a turbo-diesel engine.
Viscosity
When the number is lower, the flow of the motor oil is going to be better. A 0W20 is more fluid at engine start-up temperatures than a 5W20, but they will both work the same way at normal engine operating temperatures. Keep in mind that engine oils naturally get thicker when they cool down and thinner when they get hot.
Quality Testing
Choose an oil brand with the starburst icon and the API donut with the right viscosity grade. The starburst symbol means that the oil has passed the tests for SL service.
The API donut means that your motor oil was tested by the American Petroleum Institute and met the current SL service rating. The Association of European Automobile Manufacturers (ACEA) is the European version of API.
Location
Given that both 0W20 and 5W20 motor oils operate in the same temperature range, it is critical to consider where you will use the car. 0W-20 synthetic oil has a temperature range of -40 degrees Celsius to 20 degrees Celsius, while 5W20 synthetic oil has a temperature range of -35 degrees Celsius to 20 degrees Celsius. Having this level of specific knowledge means two things:
- If you live in an area that experiences extremely low temperatures, like Alaska or Maine, it is recommended that you use 0W20 oil in your vehicle.
- In places like Florida, where the temperature regularly tops 20°C. (68 degrees Fahrenheit), you cannot use either 0W20 or 5W20.
Mixing 5W20 with 0W20
When enthusiasts and motor oil experts are asked if this is possible, the responses are conflicting. Most professional mechanics and car owners would rather be safe than sorry, so they don’t mix 0W20 oil with 5W20 oil. SAE 0 oils are all synthetic, while 5W20 may be partly synthetic or conventional.
Even if your 0W20 and 5W20 variations are 100% synthetic, the next thing to consider is warranty and fuel consumption. Not only that, but 0W20 is very thin and made for engines made in the last ten years or so that have good durability and better performance.
Check the things you want to mix to ensure they will work together, and check your owner’s manual to see what grade of oil it can take.
NOTE: Unless it’s the only oil you have on hand, and it’s an emergency, it’s best not to mix the two kinds of oil or even switch them. The maximum viscosity is listed in the SAE J300 specifications, so 0W20 oil will always meet the requirements for a 5W20. But if you mix them, the mix will almost certainly fail the -35°C test.
Even if this weren’t the case, both 0W20 and 5W20 may have different additives that break up contaminants that regular motor oil would leave in the engine. When this happens, it could be a sign of trouble.
Oil Blends
In light of the fact that 0W20 and 5W20 include distinct additives that may not be compatible, it would be helpful to be familiar with the various oil blends and the category to which each variant belongs. Specifically, it would be helpful for you to know the following:
Full Synthetic Oil
This oil can be used in high-tech engines like those in Mercedez-Benz vehicles. It works better and lasts longer in all key areas, but it isn’t made for all engine types. They also cost a lot. All 0W20 motor oils are made of synthetic materials.
Some 5W-30 oil grades, like Pennzoil (550038221-3PK) Platinum 5W-30 Full Synthetic Motor Oil GF-5, are part of this blend.
Synthetic Blend Oil
This has a small amount of synthetic oil mixed in with organic oil, which makes it less volatile. This type reduces oil loss and makes the car use less gas. They are great for towing and going off-road. SUVs and Pickups that need to protect heavy loads often use them.
They are much cheaper than full-synthetic oils and a little more expensive than a premium conventional oil. All 5W20 motor oils, like Royal Purple 05520 API-Licensed SAE 5W-20 High-Performance Synthetic Motor Oil, are, at best, a synthetic blend.
Premium Conventional Oil
This mineral oil comes with all new cars and can be used in almost any simple engine or light-duty vehicle. Service level SM is the current name and comes in different viscosity grades. Any rating that is older than SJ is no longer useful.
High Mileage Oil
This is for older cars that have driven more than 75,000 miles. It is made up of seal conditioners that flow through the seals’ pores to help them return to their original shape and become more flexible. They have improved piston-to-cylinder clearances and a higher concentration of viscosity improvers and anti-wear additives to reduce wear.
Frequently Asked Questions
Can I use 0W20 or 5W20 for a Toyota Camry?
Follow what’s in your owner’s manual because the company that made your car knows more about what it needs than any mechanic. For example, if you own a 2009 Toyota Camry Hybrid, your owner’s manual would recommend 0W20 as your main lubricant and 5W20 as a backup.
Why does Toyota recommend 0W20 for their engine?
Toyota recommends 0W20 for three main reasons: engine efficiency, engine protection, lubrication, and reduced emission. The viscosity of 0W20 is perfect for cold starts, and it helps the engine reach its optimal temp as quickly as possible; even cold makes it less efficient.
It cuts down on wear at start-up, improves fuel efficiency, and cuts down on incomplete emissions. It also shows Toyota that the oil you’re using can last as long as they recommend between oil changes.
Should I use 5W20 instead of 0W20 for Honda cars?
What oil you use should depend on the Honda engine you have. For instance, the manufacturer recommends 0W20 oil for Civic Hybrid engines. If you can’t get 0W20, you can use 5W20 instead. If you own a Honda Accord from 2011, you can still use the 5W20.
Is it okay to switch oil brands?
Certainly! But make sure to pick an oil brand with the same API donut level as what you’ve used before. Also, make sure to follow the API category and viscosity recommendations in your owner’s manual.
What happens if I use the wrong viscosity or engine oil?
Some things that could happen are oil leaks, less gas mileage, a noisy engine, trouble starting when it’s cold, and burnt oil. You wouldn’t want the warranty to be voided because you used the wrong oil, which led to engine failure.
Will 5W20 hurt a 0W20 engine?
If the temperature outside is much lower than -30°C, it could hurt a 0W20 engine. Not only that, but because 5W20 is a synthetic blend, it could contain additives that are harmful or won’t work with 0W20 motor oil.
Can 5W30 be used instead of 0W20?
If the requirements for your vehicle demand 0W20, it is in your best interest to follow that recommendation rather than opting for 5W-30. The latter is an excellent compromise between an oil designed for high mileage and one made entirely of synthetic components, but follow the recommendation to be on the safe side.
Does 0W20 damage the engine?
Using it in an engine that can handle 5W20 will save fuel because it has less drag at the crankshaft and starts better when it’s cold. But if you use it instead of 5W-30, it will hurt your engine.
Conclusion
The difference between 0W20 and 5W20 motor oils may be minimal for the average person. But intelligent car owners and mechanics should pay attention to it. Choosing the right oil is essential for the safety and upkeep of your car because it acts as a magnet for combustion products, a shield against engine corrosion, a lubricant, and a heat pump.
Since it is the lifeblood of your engine, you should use just the appropriate oil listed in your owner’s manual or as required by your manufacturer.
