Choosing engine oil is not simply about buying a bottle with a famous brand name or selecting the most expensive product on the shelf. Every engine is designed to operate with a specific viscosity grade and technical specifications, and using unsuitable oil may affect lubrication and performance, especially during cold starts or in high temperatures.

Understanding the symbols written on the oil container and referring to the owner’s manual will help you choose the right engine oil for your car with confidence instead of relying on another vehicle’s experience or a general recommendation that may not apply to your engine.

Why Is There No Single Oil Suitable for All Cars?

Engines differ in their design, operating temperatures, and technologies used, such as turbocharging systems and emission control systems. Therefore, manufacturers specify the viscosity grade and technical requirements that match each engine. In some cases, they may allow more than one viscosity option depending on operating conditions and climate.

When searching for the right oil for your car, start with the owner’s manual or the official maintenance schedule. You will usually find information about the required viscosity grade, such as 0W-20 or 5W-30, along with performance standards or approvals that the oil must meet.

Matching these specifications is more important than choosing oil based only on the brand name.

A common mistake is assuming that an older car automatically needs thicker oil, or that hot weather always means using a higher viscosity grade. Any change from the manufacturer’s specifications should have a clear technical reason and proper evaluation of the engine condition.

How Do You Understand Engine Oil Viscosity Grades?

Viscosity simply refers to the oil’s resistance to flow at different temperatures. In multi-grade oils, such as 5W-30, the number before the letter W indicates the oil’s performance at low temperatures, while the second number refers to its viscosity when the engine reaches its normal operating temperature.

This does not mean that a higher number is always better. A thicker oil is not necessarily more protective for every engine, and a lower viscosity oil is not suitable for all vehicles. The correct choice is the viscosity grade that the engine was designed to use.

When trying to find the correct oil viscosity for your car, always check the owner’s manual first, then make sure the number written on the oil container matches the required grade.

If the manufacturer allows more than one option, review the conditions associated with each grade before making a decision.

Oil Specifications and Approvals Are as Important as Viscosity

You may find two oil containers with the same viscosity grade, but that does not mean they are identical in performance or suitability.

Different standards define oil performance levels and compatibility with specific types of engines, such as API and ACEA specifications, in addition to approvals required by certain vehicle manufacturers.

Therefore, knowing the right oil for your car requires combining both the correct viscosity grade and the required specifications.

If the viscosity is correct but the approval does not match the manufacturer’s recommendation, the oil may not be suitable for your engine.

Before choosing engine oil, compare your vehicle’s manual information with what is written on the oil container and focus on:

• The recommended viscosity grade.
• The required performance standard or approval.
• The engine type, whether gasoline or diesel.
• Special requirements for turbocharged engines if available.
• Requirements for vehicle emission control systems.
• Manufacturer recommendations for severe operating conditions.

How Do You Choose the Right Engine Oil for Your Car Practically?

Start by identifying your vehicle’s information accurately: manufacturer, model, production year, engine type, and engine capacity.

Relying only on the vehicle name may not be enough because the same model can be available with different engines, and each version may have different oil requirements.

If you want to know the correct oil type for your car, the owner’s manual is the first reference.

If the manual is unavailable, you can check the official manufacturer’s website or use a reliable source based on your vehicle and engine information.

Some people search for a website that identifies the right oil for their car by entering the model year and engine type. These tools can help narrow down the options, but it is always better to compare the results with the manufacturer’s official specifications, especially when more than one viscosity grade or specification appears.

After confirming the basic information, choosing the right oil type for your car becomes easier. Look for an oil that combines the required viscosity grade and approval, and do not rely on matching only one of them.

Do Saudi Arabia’s Climate and Driving Conditions Affect Oil Selection?

Many areas in Saudi Arabia experience high temperatures during certain periods of the year, along with dusty environments, long-distance driving, and daily city usage.

However, high temperatures do not automatically mean you should change to a different oil viscosity. You should always follow the viscosity grades approved by the vehicle manufacturer.

The vehicle manual may include a chart showing suitable viscosity grades for different temperatures or operating conditions. If more than one approved option is available, the choice should be based on the conditions specified in the manual.

Driving style also has a major impact on maintenance schedules. Frequent short trips, long periods of idling, and driving in dusty areas may be considered severe operating conditions by some manufacturers, requiring closer oil monitoring and shorter maintenance intervals.

If your vehicle is under warranty or follows a specific maintenance program, it is important to use the approved viscosity and specifications instead of making changes based on general assumptions.

Common Mistakes When Choosing Engine Oil

Incorrect oil selection does not always happen because of a lack of information. It can also result from following common advice that does not apply to every vehicle.

Some mistakes to avoid include:

• Choosing oil based only on price.
• Using a higher viscosity oil because the car has high mileage without evaluating engine condition.
• Applying a recommendation made for another vehicle to your own car.
• Focusing only on viscosity while ignoring specifications and approvals.
• Mixing different oil grades without a clear need or without checking manufacturer recommendations.
• Assuming synthetic oil always allows longer replacement intervals.
• Using products that do not provide clear viscosity and specification information.

You can explore car services and oil change solutions from Rafa when preparing for vehicle maintenance, while ensuring you know your engine information and required specifications before selecting the oil.

Frequently Asked Questions

Is 5W-30 Better Than 10W-40?

There is no single viscosity grade that is better for all vehicles. The correct choice depends on engine specifications and manufacturer recommendations because each grade performs differently under various operating temperatures.

Should I Change Oil Viscosity in Summer?

Not simply because the weather is hot. If the manufacturer allows more than one viscosity grade, you can choose between them according to the temperature range and operating conditions mentioned in the vehicle manual.

Is Synthetic Oil Suitable for All Engines?

Synthetic oil is suitable for many modern vehicles, but describing an oil as synthetic alone is not enough. The viscosity, specifications, and approvals must match the engine requirements.

What Should I Do If I Cannot Find the Vehicle Manual?

You can check the official manufacturer’s website or consult a specialized service provider using the vehicle model, production year, and engine details, then compare the recommendation with the information written on the oil container.

Is Viscosity Grade Enough to Choose Engine Oil?

No. You should consider the viscosity grade, performance standards, and required approvals together because two oils with the same viscosity grade may have different technical specifications.