What grade is SN10W40 engine oil?

1 Answers
MacChristopher
07/29/25 4:16pm
Engine oil 10W40 refers to the viscosity grade of the oil. The number before the 'W' represents the cold-start performance—the smaller the number, the easier it is to start the engine in cold weather. Common grades include 0W, 5W, 10W, and 15W. The number 40 indicates the oil's viscosity characteristics at high temperatures. Higher viscosity oils (with higher numbers) may be more suitable for high-speed driving or heavily loaded vehicles. Below is an introduction to engine oil: 1. Functions of engine oil: Engine oil lubricates and reduces friction, assists in cooling, provides sealing to prevent leaks, prevents rust and corrosion, and acts as a shock absorber. It is often referred to as the 'blood' of a car. Choosing the right oil and changing it regularly helps maintain the engine in good condition and extends its lifespan. 2. Choosing engine oil: When selecting engine oil, the most expensive option isn't necessarily the best. Instead, the choice should be based on the characteristics of the car's engine and driving habits. Engine oil can also be categorized based on winter and summer use. For winter, the primary consideration is the low-temperature viscosity grade, while in summer, due to higher temperatures, an oil with a better low-temperature viscosity grade is not necessary.
Was this review help?
9
2
Share
More Forum Discussions

Which Button to Press for Windshield Fogging?

Press the defogging button, turn on the air conditioning cooling (A/C) switch, set the temperature to the lowest, and turn on the external circulation to defog. You can use either cold or warm air to defog the car windows, but warm air is slower than cold air. The most effective method is to use cold air, which blows dry cold air directly onto the glass, preventing water vapor from condensing on the glass and achieving the purpose of defogging. The method for defogging with warm air is the same as with cold air, but note that warm air should not be used for defogging on rainy days, as it will initially increase fogging. When the car windows fog up, turn on the external circulation. The reason for car window fogging: There is a certain temperature difference between the inside and outside of the car. If the temperatures inside and outside the car are different, the surface of the side with the lower temperature will have a lower saturated vapor pressure than the surrounding environment, causing water vapor to gather on the glass surface and form tiny water droplets, resulting in fogging. Methods for defogging car windows: Air Conditioning Cooling: Use the air conditioning's cooling and dehumidifying function to reduce air humidity and remove fog. In summer, especially when multiple people enter the car and the air conditioning is not turned on in time, the high humidity of exhaled air can quickly cause the windshield to fog up. At this point, you can turn on the air conditioning to blow cold air onto the windshield, using the dehumidifying function to quickly remove the fog. If the humidity is too high and the air conditioning is not effective, you can slightly open the window to quickly reduce the humidity inside the cabin. Of course, combining this with the air conditioning will yield faster results. Air Conditioning Warm Air: Use the method of reducing the temperature difference to remove fog. In winter, blowing warm air onto the glass quickly raises the temperature of the windshield, reducing the temperature difference between the inside and outside surfaces of the glass, thereby preventing excessive fogging. However, it should be noted that the rear and side windows heat up more slowly, so it takes longer to completely remove the fog. Whether the air conditioning is automatic or manual, turning it on helps with dehumidification. The temperature control should not be set to the coldest position, as this can cause the outer surface of the windshield to fog up over time. Applying Anti-Fog Agents for Prevention: Spray a small amount of defogging agent on the car windows and wipe it clean to remove dirt and stains. While polishing the glass, a thin transparent protective film is formed, effectively preventing water vapor from condensing on the glass and forming fog, which is especially useful in cold winters. Alternatives to defogging agents include dish soap, soapy water, glycerin, alcohol, or salt water. After applying and letting it dry, wipe off any excess with a chamois or soft dry cloth to ensure the windows remain fog-free for several days. Opening Windows for Airflow: If the fog inside the car is not too heavy, you can open the windows on both sides to allow air to flow between the inside and outside of the car, reducing the temperature difference and gradually eliminating the fog. The principle of this method is the same as using cold air from the air conditioning. The downside of opening windows for airflow is obvious: it cannot be used during rain, snow, on highways, or when the fog is heavy. Rear Window Heating: Most cars have a rear window heating function, though the button location may vary. Turning on the rear window heating switch will remove the fog in about a minute.
18
3
Share

How to Drive Through Waterlogged Areas?

Prepare your ID card, driver's license, vehicle registration certificate, and other relevant vehicle documents in advance. Bring the prepared documents to the local vehicle management office and find relevant personnel to handle the business.
12
3
Share

How to solve the hard brake problem of Roewe 350?

Turn off the vehicle, use tools to remove the vehicle's brake, and check whether the vehicle's brake lacks brake fluid. Purchase the brake fluid that meets the model specifications and replenish the brake fluid.
16
5
Share

What to Do When an EFI Motorcycle Fails to Accelerate When Cold?

Before entering a waterlogged section, always check the current ground clearance of the vehicle to ensure it is not lower than the water level. Gently apply the brakes to reduce the vehicle's speed as much as possible, while ensuring the speed is not too low to prevent the engine from stalling.
12
3
Share

How to Initialize the Sunroof Function Settings on the Ford Edge?

Open and then close the driver's door, turn on the ignition, and wait for the reading lights to turn off. Press the sunroof vent switch once, press the left reading light switch once, press the right reading light switch four times, and then press the left reading light switch once again.
8
0
Share

How to Deal with Engine Oil in the Radiator?

The light flashing yellow indicates a cruise control malfunction. The light flashing yellow indicates a tire pressure monitoring system malfunction. If the light remains on for 5 seconds after releasing the brake, it indicates a brake system malfunction.
1
4
Share
Cookie
Cookie Settings
© 2025 Servanan International Pte. Ltd.