Why Do Japanese Cars Use Low-Viscosity Engine Oil
2 Answers
Japanese cars use low-viscosity engine oil because more precise components rely less on oil viscosity. Here are the functions of engine oil: 1. Lubrication and wear reduction; 2. Auxiliary cooling; 3. Sealing and leakage prevention; 4. Rust and corrosion prevention; 5. Shock absorption. Types of engine oil: 1. Mineral oil; 2. Semi-synthetic oil; 3. Full synthetic oil. Engine oil replacement method: 1. Lift the vehicle, remove the undercover, and place a 10L container under the drain plug; 2. Unscrew the drain plug, use an air gun to blow for two minutes at the oil filler port, tighten the drain plug after draining, and wipe with a tissue to check for leaks; 3. Reinstall the undercover, lower the vehicle, and use a funnel to add oil through the filler port.
I've been driving Japanese cars for over a decade and found that using low-viscosity oil is truly important, mainly for fuel efficiency. The moment the engine starts, this thinner oil quickly flows to lubricate every corner, reducing internal friction and making the ride noticeably smoother. With my daily commute, fuel consumption dropped by nearly 10%, saving me a few thousand dollars annually on gas. Engine temperature remains more stable, and cold starts in winter no longer produce rattling noises. My mechanic explained that Japanese engines are precision-designed with tight tolerances, requiring low-viscosity oil to ensure complete coverage and prevent dry friction. Always use the correct grade—stick to 0W-20 or 5W-30 as specified in the manual to avoid engine damage. Regular maintenance is equally crucial; I use quality oil and change it every six months. After ten years, my engine still runs like new. In short, it's both practical and economical—definitely worth sticking to.
