An Insight into Engine Oil Grades

The most important thing that can be used in car or taxi service is engine oil. Engine oil is one of the most important lubricants that play an important role in the combustion cycle. It keeps your engine cool and ensures that the piston rings in the IC engine are sealed in a proper manner. Let’s check out all the things that engine oil does to your vehicle.

Deliver lubrication

The engine oil lessens the friction amongst several components of the engine during the combustion cycle. By providing a thin layer of oil, engine parts do not rub each other severely. Hence, engine oil eliminates wear and tear.

Neutralize acids

When it comes to combustion, fuel and the oxidization of other lubricants produce acids. Engine oil is highly responsible for neutralizing such acids.

Clean out sludge

Engine oil plays a crucial role in ensuring that the engine block is clean and free from residue. If the engine sludge is not removed properly, it can lead to blockage.

Inhibit corrosion and oxidation

Engine oil prevents corrosion. Motor oil also protects the cylinder blocks from rust.

Hence, as you know that the engine oil is important for the smooth running of the engine, but do you know all engines cannot work ideally with the same engine oil?

Different engines need different engine oils to operate and function in an effective manner. The car manufacturer suggests that engine oil is based on the parameters of your vehicle. You ought to understand the grade of the engine oil your vehicle needs. It will assist you in getting the best performance from your motor. High-quality engine oil will increase the lifespan of the engine.

Engine oil grades

Engine oils come in different grades. SAE has graded engine oil on the basis of its viscosity. Viscosity is the quantity that can express the internal friction of the fluid. Different types of engine oils have different viscosities at room temperature. They react in a different manner to temperature changes.

20W-40 in Engine Oil

The engine oil grade comes in the form of an alpha-numeric code. Now, let’s check out what each character means:

The first number is ‘W’ that stands for Winter and represents how the oil will react to a cold start.

In general, W represents the parameter. It says how the oil will flow in cold situations.

If the number is small, the flow will be better. For example, 5W-30 oil will have a better cold flow as compared to 10W-30 engine oil.

Different Types of Grades

0W-20: It is thinner when you start the engine. In 0W-20, the oil’s viscosity is 0 if the motor is cold. When the engine reaches its regular operating temperature, the oil’s viscosity becomes 20.

0W-30: It is engineered to act as 0 weight oil at the starting temperature and a 30 weight if the engine reaches its regular operating temperature.

0W-40: It is engineered to act as 0 weight oil at the starting temperature and a 40 weight oil if the engine reaches its regular operating temperature.

5W-30: It is the most regularly used engine oil in the Indian market. The majority of the Indian car manufacturers recommend using it.

5W-40: It is fully synthetic engine oil that can perform like 5 weight engine oil when it is cold. It acts like 40 weight oil once the engine reaches regular operating temperature.

10W-40: It is the engine oil that delivers a 10 weight performance in the cold starting temperature.

Depending on the need of your vehicle and suggested by your car manufacturer, you can find the best engine oil in India  and purchase it to improve the life and performance of your vehicle.


As a mechanical engineer turned blogger, Charlie provides readers with a technical, yet accessible look into the world of automotive engineering and design. His insightful posts make complex car technologies understandable.