Can You Use 10w30 Instead Of 5w30 In Your Car?

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So you have come to a time when you need to replace the oil on your car for the first time. You will encounter some things you might not be familiar with like 5w-30 or 10w-30. Well, the good news is that you don’t need to be intimidated by these because they are symbols you can easily get familiar with.

Understanding these numbers will mean better performance from your engine in the weather you operate your vehicle in. In this article, you will find out what these numbers mean and how you can use them to your advantage in your daily drive.

Why Is It Important To Know The Difference?

To explain it briefly, these numbers are a reference to the weight or viscosity of the oil. This is how the liquid flows in certain temperatures. The standard was set by the Society of Automotive Engineers (SAE) which is why you would often find their mark alongside these symbols.

Numbers such as 5w-30 are multi-grade oils and there are ones like SEA5w which are single grade oils. We will talk in detail about multi-grade but the same principle applies to single-grade oils.

Numbers And Viscosity

For us to determine what the numbers mean, we have to first understand what viscosity is.

Viscosity is determined by subjecting the motor oil to a set temperature, 100° Celsius which is the working temperature of engines, and how hot the engine can get when it is being used. It is then passed through a device called a viscometer. The oil is poured through the viscometer and it is timed how fast or slow it takes for it to pass.

A reading is given as it passes and depending on how quickly it goes. The reading is referred to as the SAE number. The slower the oil passes through the higher the number is given and the faster the liquid travels down, the lower the number.

Different types of oils react differently to high temperatures and thus have varying viscosity. Regular oil, like cooking oil and other types of oil used for cosmetics, tends to become thicker when it is cold and thinner when heated. In essence, the warmer it gets, the lower the SAE number, and the cooler it becomes, the higher the SAE number.

With automotive engines, the oil must be at the right viscosity so that it can lubricate the components effectively in different temperatures. Because the oil becomes thicker when the weather is cool, it will have a hard time getting started because the components will not be properly lubricated.

This is why motor oil is chemically modified to be able to have low viscosity in colder temperatures. Because of the vehicle is not used for a long time, the temperature will drop. To start the engine, the oil needs to be thinner so that it can properly lubricate the engine.

On motor oils, you will often see two sets of numbers. For example, 5w-30. These are the 5w and 30. Each number is an indication of how oil performs in extreme temperatures. 5w is the symbol for the oil’s viscosity in cold temperatures and 30 is the viscosity of the oil in hot temperatures.

The Importance Of These Numbers

Understanding what these numbers indicate can prove to be beneficial to car owners and even fleet managers. This is because oils directly affect engines. For one, the viscosity will affect the heat generated by the bearings and cylinders in the engine. It will also affect how fast oil is consumed. As previously mentioned, the viscosity of the oil also affects how easily an engine can start in cold or hot weather conditions.

If the oil has a higher viscosity in higher temperatures, then the engine will use less oil. That will protect the vehicle from wear and tear. On the other hand, thinner viscosity will also improve the fuel efficiency of the engine.

Difference Between 5w-30 And 10w-30

As we have learned above, there is not a lot of difference between 5w30 and 10w30. Both have low viscosity grades which can improve the consistency of the oil depending on the situation of the vehicle engine.

SAE 5w-30 will perform better in cold weather conditions because it is thinner and more ideal if the car owner lives in colder regions. Both have the same viscosity consistency in higher temperatures. For easier reference, the W in the symbol stands for “winter”.

According to this site, so when considering using 10w-30 in the place of 5w-30, take note if the weather in your area does not have prolonged cold temperatures or does not drop below the threshold of the oil you’re using. This is why location is one of the more critical considerations to make when choosing between 5w-30 and 10w-30.

The best indicator of the ideal oil to use for your car is specified by the manufacturer. Most manufacturers do recommend different oil viscosity so that the car owner can use which one is the most ideal for their environment. Referring to your owner’s manual can help you choose which one is the best for your vehicle.

A 5w-30 oil has a viscosity grade of 5 at cold or low temperatures and grade 30 at higher temperatures. These are used for light-duty engines and are preferable for cars in cold climates because it allows the oil to flow throughout the engine.

On the other hand, a 10w-30 oil is more common as it is designed to help regular petrol or diesel automotive engines. Although it is suited for cold weather operation, it performs better in hot weather or for vehicles that need to haul heavy loads or are used in heavy-duty applications.

Changing Oil In Your Car

Oil change is one of the most basic and effective maintenance services you can perform to keep your car working well and having a long service life. In this section of the article, we will provide you with a quick and simple step-by-step guide to changing the oil in your car.

Step 1: Jack Up the Car

Make sure that you do this safely. Never go under the car without it being properly raised by a lift. You should have good visibility of the components you need to remove.

Step 2: Drain It

Find a bucket where you can drain the oil. About 5 gallons would be enough. Use the right tools to remove the plug and make sure to store it properly. You don’t want to lose it because it will be quite difficult to replace.

Step 3: Close It Up

Once all the oil has been drained, it’s time to close the plug. Do not overtighten it. Seal it just enough so that it is properly closed. Check to see your owner’s manual if they have additional instructions when replacing the drain plug.

You should also replace the oil filter to increase the service life of the oil you just used. Like the plug, use the proper tool to safely remove the filter. Allow the excess oil to drain before replacing it with a new one. Apply a light coat of oil on the edge of the rubber gasket of the oil filter to provide a good seal when you tighten the filter.

Step 4: Fill It Up with New Oil

You can now let the car settle on the floor. Open the hood and fill the engine with new oil. Use a funnel to keep the operation clean and precise. Make sure to fill the engine up with the proper volume of oil recommended by the manufacturer.

Once you’ve filled it up with oil, check for leaks and see if the oil is at the proper level. Use the dipstick to see if it reaches the proper level. A good rule of thumb is to fill it with less because it is easier to top it up with more than to reduce it once you’ve closed everything beneath the car.

Step 5: Clean Up

Sometimes, an oil change can be messy. If you are doing it in your garage, any oil spill should be addressed properly. Wipe the engine for any excess oil or dirt as well.

Frequently Asked Questions (FAQs)

Which Oil Is Better 5w30 Or 10W30?

5w30 is mostly used for light-duty engines while 10w30 is used for engines that need to perform at a higher rate. This is because if the engine exerts a lot of effort, it will have a higher working temperature. 10w30 will provide the proper sealing and protection the engine needs at that rate of performance.

Can You Mix 5w30 With 10w30?

While it is relatively safe to mix the two types of oils, it is not recommended to do so. Mixing two types of oils may affect engine performance and decrease the time before your next oil change. Even if this will not trigger damage to your engine but it would affect the warranty coverage of the oil. So, if the car is still under warranty, it is not advisable to mix different oils because that would void the warranty.

Can I Use 10w30 From 5w30?

If you’re considering changing from 5w30 to 10w30, you might not really find a whole lot of difference. The first thing you need to check is the manufacturer’s recommendation.

The only difference between the two oils is that the 5W30 is better for cold weather that reaches below 0 degrees Celsius. But if it doesn’t go below that, then it is changing and it will not produce much of an effect.

As a rule of thumb, always go for what the manufacturer recommends and just do the regular maintenance of changing oil and filters as prescribed by your mechanic.

Does Oil Type Affect Fuel Economy?

While the type of oil can have an effect on how much your vehicle will consume gas, it is not the sole factor that affects your gas mileage. Changing oil regularly will have a positive impact on your vehicle. This is because oil has an expiration date. What that means is that as it is used over time, it becomes less effective in keeping your engine lubricated and cool.

The heat damages the molecules that affect the viscosity of the oil. Without the proper viscosity, the lubrication capability of oil is compromised and it can become useless and thus affect gas mileage.

If neglected further, oil can build up resulting in sludge which can not just affect gas mileage but other effects that can shorten the service life of your car.

Is Thicker Oil Better For Cars With High Mileage?

Some oil manufacturers make specific products that cater to the needs of high-mileage drivers. These are designed to prevent oil leaks which is one of the most common problems of those who drive for long periods of time and farther distances.

The leak is caused by the breaking of seals and gaskets. These types of oils are produced with conditioners that rejuvenate these components. Some recommend using oils with high viscosity like 10w-30 to help with preventing leaks because thicker oil tends to have more pressure in pushing the motor oil through the seals and gaskets.

Additionally, thicker oil is better for older cars because it can improve the overall oil pressure in it and helps protect the engine bearings better compared to, say, a 5W viscosity.

Here’s a cool video explaining engine oils:


Different types of engine oils have different characteristics. The most important consideration when choosing between a 5w-30 and 10w-30 oil is your location. A lower viscosity oil will perform better in colder regions and will provide better performance for your car when it starts.

If you would go for a 10w-30 oil, it will also provide you with a good start provided that the temperature does not drop below 0 degrees. Another benefit you can get is that it will have better protection for your car engine on long drives.

Referring to the owner’s manual for the ideal viscosity of oil for your car is the simplest way to determine which one is most preferable for it.

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