What are oil viscosity numbers?

The higher the number, the thicker the oil. The lower the number, the thinner the oil. For example, a rating of 5W-30 means that the oil will have a viscosity rating of 30 at 212℉, or 100℃, (an engine's average operating temperature).

What do the viscosity numbers mean on oil?

The number preceding the W designates the viscosity at a low temperature, and the number following represents viscosity when the engine is hot. For example, a 10W-30 motor oil 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.

Is 5w30 or 10W30 thicker oil?

So both the oils 5W–30 and 10W–30 have exactly the same viscosity (SAE 30) when your engine is running, and will perform in the same way. However, the 10W–30 oil will be thicker (higher viscosity) than the 5W–30 when it is cool.

Is 30 or 40 thicker oil?

The higher the number, the more viscous or thicker, the oil is at higher temperatures. This means that at 100^oC, 10W30 engine oil has the viscosity of an SAE 30 single grade oil, and 10W40 oil has SAE 40 viscosity. 10W40 oil has a higher viscosity, retaining more thickness than 10W30 as the temperature rises.

What happens if I put 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.

Engine Oil Codes Explained, SAE (Society of Automotive Engineers) numbers - Oil Viscosity Explained

What happens if I put 10w40 instead of 10W30?

Between a 10W-30 and 10W-40, 10W30 motor oil would run smoother in colder climates while a 10W40 would be more effective in preventing engine wear and tear in warmer temperatures.

Is high or low viscosity better?

This is important, as engine oils naturally thicken as they cool and thin as they are heated. Thin, low viscosity oils flow easier to protect engine parts at cold temperature. Thick, high viscosity oils are typically better at maintaining film strength to protect engines at high temperatures.

Is higher or lower viscosity index better?

Viscosity index diagram

The slope of the lubricant with a high VI is more horizontal: the viscosity remains more stable across a wider temperature range. This means a lubricant with a higher viscosity index is more desirable, because it provides a more stable lubricating film over a wider temperature range.

Which oil viscosity is best?

For very cold weather, a viscosity rating of 5W-30 provides maximum protection. When driving in temperatures running from 0 to 60 degrees Fahrenheit, a rating of 10W-30 offers excellent all around protection. For driving in extremely hot conditions, 20W-50 oil offers the best protection.

What happens if I use 10w30 instead of 5w30?

Both 5w30 and 10w30 engine oils have a similar SAE rating, meaning that they will perform the same at high or operating temperatures. The digits 30 indicates the viscosity of the oils when in high temperatures. 10w30, however, will thicken more when in a cold climate. 5w30 is much suitable during the cold season.

Should I use thicker oil in an older engine?

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.

Is 10w40 thicker than 5w30?

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. At high temperatures, the 5w30 oil is thinner than that of 10w40 since 30 is lower than 40.

Is 10w30 thicker than 10w40?

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.

Does higher number mean higher viscosity?

In the simplest terms, viscosity refers to how well a lubricant flows at a given temperature. The quicker an oil flows, the lower its viscosity and the grade assigned to it by the Society of Automotive Engineers (SAE). High viscosity oils flow more slowly and come with a higher SAE number.

Which oil is thicker 5W-20 or 5W-30?

So, due to viscosity, 5w20 is a thinner oil during operating temperatures, whereas 5w30 is thicker during operating temperatures. A majority of manufacturers are now producing engines that operate on 5w20 oil, to which it's important to stick to this viscosity and not substitute 5w30.

How do you read a viscosity chart?

Again, the lower the number, the lower the viscosity of the oil and the faster the oil will move around the engine. As an example, let's compare 5W-20, 5W-30 and 10W-30 motor oils. A 5W-20 and 5W-30 will have very similar if not equal viscosity at lower start-up temperatures.

What is viscosity index in simple words?

Definition of viscosity index

: an arbitrary number assigned as a measure of the constancy of the viscosity of a lubricating oil with change of temperature with higher numbers indicating viscosities that change little with temperature.

What is the viscosity scale?

In layman's terms, viscosity defines a fluid's resistance to flow. The higher the viscosity of a liquid, the thicker it is and the greater the resistance to flow. Temperature will affect the viscosity of most materials.

Is 20w50 thicker than 10W40?

10w40 oil is a popular all-purpose oil designed in many different engines. 20w50 (also known as 10w30) is another popular all-purpose oil used in engines. The differences between 10w40 and 20w50 are small, but they have something in common: They are thicker than regular 20w50 oil.

Which is better 5w30 or 5w40?

5w30 can be used by different type of vehicles and in different range of temperatures, but is ideal for colder temperatures. 5w40 is often used in higher mileage engine sand performs better in warmer temperatures.

What is considered low viscosity?

Fluids with low viscosity have a low resistance and shear easily and the molecules flow quickly; high viscosity fluids move sluggishly and resist deformation. Some liquids, like pitch, glass and peanut butter, have such high viscosity they behave like solids.

Which engine oil is best for hot weather?

The ideal motor oil for your car is one that can withstand the hottest temperatures in your region while still being able to flow when the weather is at its coldest. SAE 5W30 oil is suited to a broad range of temperatures, making it one of the most commonly used oils on the market.

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.

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.