The first number in the oil classification refers to a cold weather viscosity. … For example, a 5W- motor oil will flow better at lower temperatures than a 15W- motor oil. The higher number, following the “w” refers to hot weather viscosity, or how fluid your oil is at hot temperatures.

Is 5w30 oil thicker than 10w30?

Is 10w30 thicker than 5w30? 10w30 is thicker than 5w30 because it has a higher viscosity in low temperatures. The engine oil will flow slower than 5w30 during the cold season. … Thicker oil offers better lubrication of motor and engine parts.

What are the different grades of oil? The 11 viscosity grades are 0W, 5W, 10W, 15W, 20W, 25W, 20, 30, 40, 50, and 60. In the United States, these numbers are often referred to as the “weight” of a motor oil, and single-grade motor oils are often called “straight-weight” oils.

Which is better 10W40 or 20W50?

10W40 is not better than 20W50 for high mileage. The difference between 10w40 and 20w50 is simply that the latter is thicker. As far as gas mileage goes, no oil will improve your gas mileage by changing from 10W40 to 20W50 or vice versa.

Which is better 5w30 or 5w40?

The difference between 5w30 and 5w40 is that 5w40 has larger viscosity than 5w30. This means 5w30 is better than 5w40.

Should I use thicker oil in a high mileage engine?

High-mileage motor oil doesn’t hurt and it could prevent leaks from starting. … Some mechanics recommend switching to a thicker (higher viscosity) oil — such as 10W-30 full synthetic oil instead of 5W-20 full synthetic — or using oil additives to stop leaks.

Is 5w30 good for high mileage?

Amazon Basics Full Synthetic is the best 5w30 oil for high mileage vehicles. This oil should only be used on vehicles exceeding 75,000 miles. This motor oil is formulated for longer drain intervals. It helps in preventing a build-up on drain intervals and preventing rust and corrosion.

What does the 30 mean in oil?

The short answer:The numbers represent the viscosity of the oil and the W stands for WINTER. … In a 5W-30 for example, the number before the W describes the viscosity of the oil at low temperatures. The lower the number, the thinner the oil and the better the oil’s cold temperature/ cold start performance.

Is Thicker oil better for older engines?

Newer vehicles can utilize thinner oils for faster lubrication of new engine parts. In contrast, older, high-mileage engines benefit from thicker oils to prevent friction and oil loss.

Can I use 10w40 instead of 5w30?

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.

Will 20W50 hurt my engine?

Will 20w50 hurt my engine? A 20W/50 oil is much thinner at high temperature than a 5W/30 at a low temperature, so the viscosity will not hurt your engine.

Is it OK to use 20W50 oil?

20W50 motor oil is suitable for warmer climates, where the higher temperature causes the oil to thin. It is also useful for vehicles subject to hot temperatures and for those used for high-stress activities such as hauling or pulling trailers.

Is 20W50 good for high mileage?

20W50 is not necessarily better than 10W40 for high mileage. If you are asking about needing a thicker oil for high mileage, the answer is no.

What happens if I use 5W40 instead of 5w30?

In practice, this means that each oil is just as viscous at lower temperatures and will remain viscous at -30°C, however 5w40 oil outperforms 5w30 oils at higher temperatures, being effective up to ambient temperatures of 50°C, as opposed to 30°C.

Is it OK to mix 5w30 with 5W40?

Mixing different oils will not improve the performance or efficiency of the engine in any way. The additives in synthetic oil may have limited or no effect at all when mixed with a regular engine oil. … You can use 1 litre of 5W30 mixed with 5W40 and it will not cause any sort of ill effects to the engine.

What does 5W 30 stand for?

5w30 is a motor oil that is widely used in light-duty petrol and diesel engines. … The “W” stands for “winter,” the number preceding it indicates the oil’s viscosity (or thickness) at low temperatures (hence the W), and the number after it indicates viscosity at higher temperatures, when the engine is running.