Should the Vios use 5W20 or 5W30?
2 Answers
The Vios uses 5W20 engine oil. Below is more information about engine oil: 1. Mineral oil: Mineral oil is the residue left after gasoline and heavy oil are extracted from petroleum. Although it is a natural oil, it contains more impurities. It is cheaper compared to semi-synthetic and full-synthetic oils but provides poorer lubrication for the engine and has a shorter service life. 2. Semi-synthetic oil: Semi-synthetic oil is a middle ground between mineral oil and full-synthetic oil. It contains a large amount of anti-corrosion additives to improve the stability and high oxidation resistance of the oil. 3. Full-synthetic oil: Among these three types of oil, full-synthetic oil offers the best quality and durability. It is also the most expensive type, typically maintaining its quality for 10,000 to 12,000 kilometers in general passenger cars. 4. Hazards of water in engine oil: If a small amount of water enters the engine and mixes with the oil, the oil quality deteriorates. Oil containing water increases wear on engine components, potentially leading to increased engine noise and vibration during future vehicle operation.
I highly respect the recommendations in car manuals. The Vios owner's manual explicitly specifies using 5W-20 engine oil, especially for newer models. This viscosity provides better fluidity during cold starts, reduces engine wear, and improves fuel efficiency. While 5W-30 may work fine in some hot climate regions or for high-mileage vehicles, it's not the preferred choice. I recommend strictly following the manual's guidance and avoiding arbitrary specification changes. Oil selection is crucial for engine longevity, and regular oil level checks are equally important. If unsure, consulting professional technicians at a 4S shop is the safest approach—don't risk damaging core components to save small costs.
