What does 10w40 mean?

10W-40 is the viscosity, or weight, of the motor oil as defined by the Society of Automotive Engineers (SAE for short). A 10W-40 oil has a viscosity grade of 10W at a low temperature and 40 at a higher temperature. What does this mean, exactly? Motor oil thickens when it's cold and becomes thinner when heated up.
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Which is better 5w30 or 10W40?

The 5w30 oil will flow better at low temperatures than the 10w40 oil. This means that the 5w30 oil will protect the engine better at low temperatures, usually when the engine is just starting or during weather conditions such as winter.
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Is it OK to use 10W40 instead of 10w30?

The short answer is yes. Because both oils are formulated to give the same performance, it will be safe for you to use either oil. Some differences between the two oils include viscosity and base oil.
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What is 10W-40 motor oil good for?

Higher viscosity oil such as a 10W-40 can be useful for older engines burning or leaking oil. We offer Mobil™ 10W-40 high viscosity motor oils for use in vehicles with more than 75,000 miles, and a synthetic blend oil when cost is a consideration.
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Is 10W-40 too thick?

A low viscosity oil will move quicker through the engine to keep it lubricated and cool. Additionally, if your engine has a lower running temperature, 10W-40 motor oil might be too thick. Its higher viscosity at running temperature can reduce engine effectiveness as it'll need more energy to keep the engine operating.
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Castrol 10w-40 oil explained | Which oil for my car? | Castrol U.K.



Is 10W40 fully synthetic?

Semi-synthetic oils such as 10W40 have long been the standard. Their base is refined crude oil, which is then blended with additives.
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What does the W mean in oil?

The “W” that you see on oil labels stands for the word "Winter" because this portion of the label shows the viscosity level of oil when an engine is cold. Motor oil that is thinner can flow more easily and faster. This is important because when you start a cold engine, the oil needs to lubricate the equipment quickly.
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Is 10W-40 OK for my car?

Your vehicle does not use 5W-30 oil. The recommended oil viscosity for your vehicle, according to Kia documentation, is 10W-40. If you drive the vehicle in exceptionally cold weather, well below 32 degrees, you can use 5W-30 oil but even 10W-40 is still perfectly OK to use if outdoor temperatures are below freezing.
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Is 10W-40 oil OK for petrol engine?

Redex 10W-40 Part Synthetic Oil is a high-quality engine oil suitable for both petrol and diesel vehicles, including those with fuel-injected, multi-valved and turbo-charged engines.
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Is 10W40 good for high mileage?

Designed for high mileage vehicles

Mobil 1 High Mileage 10W-40 motor oil is recommended by ExxonMobil for use in high mileage vehicles (even those that have used lower quality conventional oils), including: Cars. Trucks.
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Is 10W40 good for winter?

Is 10W40 good for winter? Generally, the answer to this is yes, since it is a low-temperature oil grade.
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Which is thicker 10W 30 or 10W 40?

The difference between 10W-30 and a 10W-40 is the high temperature viscosity. Obviously, a 10W-40 is thicker than a 10W-30 at high temperature.
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Is Thicker oil better for older engines?

A: Yes. This is a practical method to improve oil pressure in an older, high-mileage engine. The slightly thicker oil film from the heavier base weight oil - 10W - can help protect worn engine bearings as well.
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Will thicker oil damage my engine?

Using oil that is thicker than recommended may lead to a decrease in fuel economy, a higher load on your engine, and even a shorter life for your engine. Conversely, using thinner, lighter-weight oil than recommended can cause excessive wear and shorter life.
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Is 10W thicker than 5W?

A 10W or 5W is the index for how easily the oil flows in winter (hence the W). A 10W oil thickens more than a 5W. The other number indicates the oil's resistance to thinning at high temperatures.
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What happens if you put too thick oil in a car?

If the oil is too thick (aka, the viscosity is high), your car may not start in cold temperatures (cold weather places more strain on a vehicle in any case). When this happens, the thick liquid can't properly lubricate every part, and it creates enough resistance to impair the most important function–ignition.
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How long does 10w40 oil last?

Simply put, the shelf life of conventional motor or "lube" oil is up to five years.
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Will the wrong oil damage my engine?

Cause damage to engine life

The wrong engine oil can cause engine damage because it does not properly lubricate its components. This will lead to metal-on-metal contact since the moving parts are not being lubricated. Friction quickly follows, causing engine parts to wear.
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What happens if you use the wrong oil?

You might notice a few oil spot in your garage or under your car because using the wrong oil can lead to leaks, or you might become aware of a burning smell while driving. If the oil isn't working as it should engine parts might not be lubricated well enough and cause friction, which can burn the oil.
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Can you use 5W 30 instead of 10w40?

Can You Mix Car Oil 5w30 And 10w40? The oil that performs better in the cold than 10w40 is 5w30, but less good cold than 10w40, and that has a viscosity that is higher than 5w30 but lower than 10w40. The engine will not be improved by mixing different oils.
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What is 10W oil used for?

10W-30 motor oil makes for a decent high-mileage oil. It gives a better fuel economy while reducing the oil consumption for older engines. Older engines with more than 75,000 miles on them require a thicker oil that will properly lubricate their critical engine parts and prevent oil leaks, sludge, and deposits.
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What does 20w50 mean?

SAE 20W-50 is a thicker oil with high viscosity at hot temperatures and is highly resistant to oil thinning. Despite being one of the less popular oil viscosity grades, it's still recommended for a lot of automobile vehicles.
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Which oil is better 5W 30 or 10W-30?

Suitable Vehicle Types. 5W-30 multi grade oil is ideal for private vehicles and light-duty petrol and diesel engines. It also provides a better cold temperature start than 10W-30 oil. On the other hand, the slightly thicker oil,10W-30, provides better lubrication for commercial vehicles and heavy-load engine cars.
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What does 10W-30 stand for?

For Example: 10W30

This means the viscosity is at 10W when the engine is cold and 30 when the engine is hot. Low viscosities are good for cold temperatures (hence the “W” association) because the oil is thinner. Thinner motor oil flows more easily and moves quickly.
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