What Do the Numbers on Motor Oil Mean – Get The Facts!

Have you ever gone to purchase motor oil and begin to stare at a couple of motor oil on the shelves wondering what all those numbers on the bottle mean? SAE 5W-30, 15W-40, 10W. Does it make a difference which oils go in your car? The thing is that the numbers that you see on each motor oil bottle tend to range from 0 to 60 and are properly tested by the Society of Automotive Engineers (SAE).

Even if it’s a case where you’ve brought your car to a professional to get the oil changed, they will put a sticker on the windshield so that you can have an idea of the oil they used in your vehicle.

It’s safe to say that the number before and after the W represents viscosity. The letter W stands for winter. As you may already know, viscosity means the thickness of the oil. The need for different grades of oil is essential when the weather changes because the temperature has a dramatic effect on the viscosity of the oil.

It’s best to keep in mind that 40-weight oil may be the perfect choice for a long road trip in the summer holiday when it’s hot, but will eventually turn to sludge in the cold winter season. On the other hand, the 5-weight oil is the best option in the winter season but provides little to no lubrication after the snow melts.

What Do the Numbers on Motor Oil Mean

What Do the Numbers on Motor Oil Mean

The First Number

It is said that the number to the left of the W stands for the oil viscosity when the temperatures are low. While the number that’s located to the right of the W stands for the viscosity for the hotter temperatures.

If it’s a case where the first number is low, then it’s an indication that the oil is thin. Whenever the weather condition is cold, it’s always best to have thin oil in your engine. Having thick oil is a bit challenging since it will have a hard time flowing throughout your engine and lubricating its components.

The Second Number

The Second number tends to vary based on two different factors; the temperature of your engine and the heat of your environment. If it’s a case where you live in an environment where the heat is hot, you will definitely want this number to be on the higher end since it means thicker oil. It’s always best to have thick oil in hot temperatures because it will do a wonderful job of lubricating the engine components.

The two most popular oils in the United States are the 10W-30 and 10W-40. However, if you reside in a country that has very cold weather, then it’s best to go with a thinner oil like the 0W-30.

If you take the time out to check the owner’s manual of your vehicle, it will tell you the viscosity oil grade that you are supposed to use. The thing is that the manufacturer doesn’t always take into the mind where you live which can be bad.

This is why it’s important to know the various types of motor oils so that you can make your own decision on the best motor oil for your needs.