what is sae on oil

If you’ve ever bought motor oil before, chances are you’ve seen the label SAE and you’re not sure what it means. Before you buy oil for your car, knowing that the oil is right for your engine is crucial. Engine oil allows your car components to stay functioning and it helps them to continue running for a long time. Your car has a lot of moving parts and when they rub against each other, a lot of heat is created. Using the correct oil in your car will lubricate those moving parts and will absorb their heat energy. By reducing the amount of friction these moving parts are making, the heat is spread out through your engine rather than staying concentrated in one place.

What is SAE?

On your motor oil, SAE stands for ‘Society of Automotive Engineering’. SAE is a code system that grades motor oils based on their viscosity. The viscosity of the oil is the measure of its thickness and how long it takes to flow through the containers. If an oil has a high viscosity, then it takes longer to flow through the container. If an oil has low viscosity, then it will flow quickly through the container.

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On the oil container, the SAE is writing in the format ‘XW-XX’. For example, SAE 10W-50, SAE 10W-40, SAE 10W-30. Looking at letters within the SAE codes will let you know more about the oil. In the SAE codes, the letter W is short for winter – people mistake it for it meaning weight which is not the case. W means that the oil will start to flow at – degrees Fahrenheit which is -17.8 degrees Celsius. The low the W numbers in the SAE codes, the lower the viscosity of that oil during winter or 0 degrees Fahrenheit. The higher the W number, the more viscous the oil will be at 0 degrees Fahrenheit. If you need something to gauge this with, for cold countries, you want to have a low W number – something between 0W and 5W would be ideal.

After the W, there are two XX that follow – W-XX. The numbers that fill in the XX is the viscosity of the oil when it’s measure at a temperature of 212 degrees, or 100 degrees Celsius. This will give you an idea of how thin and quickly the oil will flow when it’s at a high temperature. The low the number is that fills in the XX, the less viscous it’ll be. For example, an oil labeled 5W-20 will be less viscous and flow quicker at a high temperature compared to an oil grading that’s 5W-50.

Continued Explanation for SAE

The SAE is an organization that continues to grow and evolve and so has their involvement in the auto industry. In different fields such as the aerospace field, cars, petroleum, and trucks, the SAE provides the best global standards for oils. The SAE makes high-quality oil that meets the same standards throughout the world. Depending on where you are in the world, whether it be Nigeria, or New York if you bought a graded oil of 5W-30, the quality will be the exact same.

If the SAE weren’t in existence, it’s likely that there would be various different oil standards across the world meaning that you could get different quality oils and you won’t be able to tell the quality of your grade if you weren’t a frequent blog trotter who drove a lot. There may have even been different standards across the country so luckily there’s an organization like the SAE that provides and maintain a standard across the globe.

Single Grade and Multi-Grade Oil

Single grade oil doesn’t use a viscosity modifier additive and it can only have 11 viscosity grades due to it only being a single weight oil. Out of 11 of these grades, only 6 of them have a W label meaning that their viscosity hasn’t been tested at a low temperature. The 11 grades are OW, 5W 10W, 20W, 20, 30, 40, 50, and 60. Single grade oils are also known as straight weight oils because they have a set number of grades.

Multi-grade oils on the other have a larger temperature range at which they can be exposed to and still remain at a high quality. During your engine’s high temperature, some engine oils which be highly viscous and during the low temperatures, some engine oils will be less viscous. Since this range is too high and it needs to be more balanced, a polymer called viscosity index improver is used. These are oil additives that can allow engine oils to be used at a different temperature so when your engine is at a high temperature or running at a normal temperature, it will still perform the same.

Most engine oils will require the use of multi grade oils because they support a wider range of oil temperatures and the engine’s temperature within most cars will fluctuate a lot throughout the year. Single grade oils are no longer used in modern engines because of the high difference between their viscosity when being used at a high temperature and at a low temperature. The only cars that will still be compatible with single-grade oil will be old vintage cars that were manufactured decades ago and have engines that function with single-grade oils. Cars with old engines usually don’t fluctuate between extremely high temperatures and extremely low temperatures during the year. Single grade oils are used in things like lawn mowers because the engines of a lawnmower don’t have extreme fluctuations.

Oil Viscosity

The SAE has one job and it’s to make sure that there’s a standardization of petroleum and oil around the world. There’s a testing program that makes sure all the products have the same attributes. Viscosity is the measure of resistance flow.

Oil that’s graded with 5W-30 is going to remain at a low viscosity when being used in the high summer heat and the cold of winter. This means that at an extremely low temperature of 30F, the oil will still be able to flow smoothly, and the quality won’t deteriorate. And at high temperatures like 212, the oil will still be able to protect the engine and prevent overheating.

With SAE numbers, you’ll usually see 30 as the XX because the SAE testing program is centered around 30 as a viscosity number. When an oil is at 35F and keeps a weight of 30, this oil will be described as multi-grade oil, therefore, it’ll be given a grade of 5W-30. This suggests that the oil will remain at a low viscosity when in cold winter temperatures and at a low viscosity weight of 30 when being used in high temperature.

How Engine Oil Works

The engine oil that you put in your engine works as a lubricant that allows all of the engines component to run past each other with less friction. This stops the engine from overheating which will improve the longevity of the engine. It also works as a clean and it goes around the engine’s components and collects debris that has been scattered throughout the engine. Without this, your engine can clog up and overheat due to the debris.

Engine oil is made up of base oil and a number of additives. The purpose of the base oils is to lubricate the engines moving parts and to reduce the amount of friction and heat they produce. The additives in the oil keep it thick and maintain its thickness under different temperatures. This will help to break down any dirt and dust that could corrode the engine.

If You Don’t Check Your Oil, the Engine will Fail

If you want to ensure that your engine has longevity, you’ll need to make sure that you’re putting the right oil and doing the right checks on the engine. There’s a lot to know about oil such as the quality, additives, consistency, brand, and temperature that can all affect the way the engine runs. Failure to maintain the engine by putting in the wrong oil can cause the engine to deteriorate quickly. The key to a long-lasting engine is maintenance. Oil is just one form of engine maintenance and even this needs to be done right. Failure to main your vehicle as a whole can lead to all sorts of problems.

If you want to avoid engine problems or any other problems and save $100s of dollars that you’ll spend at the auto repair shop, you’ll need to service your vehicle often – you can use our mechanic-rated Auto Maintenance and Repair Manual to do this. It’s basically what mechanics use to go through your vehicle to check if there are any problems that need fixing. As soon as they notice the most minor problem, they’ll ask you to fork out some money even though it’s a problem you can fix yourself in minutes – the manual will teach you how to maintain your vehicle every few thousand miles and it’ll teach you how to fix minor problems that mechanics will ask you to pay for; saving you money in the long run.

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Different Types of Motor Oils

There are different types of oils that can be used in your car’s engines and they all multi-grade oils because of their ability to still remain at a good viscosity and high quality whilst your engine goes through different temperature changes. The most common grades for an oil are 5W-20, 5W-30, and 10W-30. These grades mean that the oil manages to maintain a low viscosity when the temperature is low and in high temperatures. This is indicated by the low Weight number and the low viscosity when used at a temperature of 212 degrees Fahrenheit.

Conventional Oil

Conventional oil is the most common type of oil there is on the market. This is due to its low price and it follows the standards of the SAE and API. Conventional oils aren’t rich in additives which means their quality may deteriorate when being used at a high temperature. If you need a quick and cheap oil change, using a conventional oil would be useful for your engine.

Premium Conventional Oil

Premium conventional oil is the most commonly recommended oil that car manufacturers recommend. If you look at your car’s manual, chances are that premium conventional oil is being recommended. This type of oil has widely used grades, and this includes 5W-20, 5W-30, or 10W-30. This means that they can maintain good quality when your engine’s temperature is fluctuating throughout the year.

Full Synthetic Oil

Full Synthetic oil is at a higher quality than conventional oils and they’re specifically made for high tech engines that require more performance. This is usually sports cars or cars with a lot of horsepowers. This type of oils allows the engine’s components to stay lubricated therefore preventing the engine from overheating when being used. They have to go through specialized tests and provide a high viscosity level. This will prevent the oil from breaking down at extreme temperatures and prevent oxidation. Full synthetic oil can also give cars a better power which means improved horsepower and better fuel efficiency. Due to the high quality and properties of this oil, they are more expensive, but this is justifiable due to the benefits it’ll provide and the longevity that comes with it.

Synthetic Blend Oil

Synthetic blend oils are oils that are mixed with a synthetic oil and a premium conventional oil. This means that the oil will remain at a high quality when reaching extreme temperatures and it can be used to improve the car’s fuel efficiency. This type of oil is usually recommended for SUVs and pickup trucks as it provides protection and lubrication in heavy engines.

High Mileage Oil

If your car has a high mileage after you’ve tested it with an odometer, you should be turning to a high mileage oil. This type of oils provides protection to engines that have been used for a long time. It makes sure that the engines still have longevity due to its properties.

Drawbacks of Using Additives to Improve Viscosity

In multi-grade oils that need to perform at a high quality during high temperatures, polymers are used to improve the viscosity so it can remain at a high quality even when the engines fluctuating in temperature at different times of the year. The downside to using additive in your engine is that they can cause sludge – this is the dirty stick grease-like substance that’s formed due to oxidation and contamination of the oil in your engine.

Due to the inevitability of sludge building up in your engine due to the contamination of the oil, oil manufacturers are looking for a way to develop oils that maintain a good quality without the need for additives. If you want to use an oil additive on your engine, there are some high-quality oil additive (View on Amazon) that you can find on the market.

Most Common Type of Additives Found in oils are:

  • Viscosity index improvers to stop the oil from thinning.
  • Friction modifiers to reduce friction.
  • Detergents to remove sludge and carbon deposits.
  • Anti-wear to protects the piston rings, cylinder walls, lifters and cams.
  • Dispersants to absorb contaminants that could damage the engine.