What is the difference between 0W20 and 0W40 engine oil?
2 Answers
The difference between 0W20 and 0W40 engine oil lies in their kinematic viscosity: 0W20 oil has a kinematic viscosity of 8 to 9 centistokes at 100 degrees Celsius, while 0W40 oil has a kinematic viscosity of 12 to 15 centistokes at the same temperature. The functions of engine oil include: lubrication and anti-wear, assisting in cooling, cleaning, sealing to prevent leaks, rust and corrosion prevention, and shock absorption. The method for changing engine oil is as follows: 1. Lift the car, remove the protective plate, and place a container of about 10 liters under the oil drain screw; 2. Loosen the oil drain screw, use an air gun to blow for two minutes at the oil filler port, tighten the oil drain screw after draining, and wipe it with a tissue to check for leaks; 3. Reinstall the protective plate and lower the car, then use a funnel to add new oil through the oil filler port.
The difference between 0W20 and 0W40 engine oil is quite significant. As someone who has been driving for over ten years, I feel this has a lot to do with seasons and driving habits. 0W20 flows faster at low temperatures, making winter starts particularly smooth without any knocking sounds, and the engine warms up quicker. On the other hand, 0W40 has higher viscosity at high temperatures, offering better engine protection during long summer highway drives, preventing excessive wear. I've tried using 0W20 in congested city driving, and the fuel efficiency is noticeably better. But if you frequently drive at high speeds or haul heavy loads, 0W40 is more durable. However, remember to stick to what your vehicle's manual recommends—switching randomly could harm the engine. Also, make sure to check the oil regularly to ensure it's clean. Driving location matters too; 20 is more convenient in cold northern regions, while 40 is safer in hotter areas.
