Vios comes with 0W20 factory-fill oil – Toyota's specialized engine oil. For subsequent maintenance oil changes, you can choose from brands like Mobil, Castrol, Shell, or Dusuo Lubricant. The official Vios manual recommends oil specifications of 0W20, 5W20, or 5W30. Oil viscosity changes with temperature, so special attention should be paid to its performance under both low and high temperatures. For example, in 5W-30: the first number indicates low-temperature fluidity – 5W means it can withstand temperatures as low as -30°C. The smaller this number, the better the low-temperature fluidity, resulting in smoother cold starts for the vehicle. The latter number represents the oil's kinematic viscosity at 100°C – higher values indicate better ability to maintain viscosity under high temperatures, which can also be understood as better lubrication performance under high-temperature conditions. The oil change procedure for Vios is as follows: Wait for the engine temperature to cool down, allowing the oil to flow back to the oil pan; Loosen the drain plug with a wrench and use an oil pan to collect the old oil until the flow stops completely. Start the engine and let it run for 30 seconds to allow oil in the main oil gallery to drain out; Remove the oil filter using a specialized wrench; Apply oil to the gasket of the new oil filter and hand-tighten it clockwise; Add new oil through the engine valve cover filler port – typically about three-quarters of a standard oil bottle; Start the engine and let it run for 5 minutes, then check for leaks around the drain plug and oil filter. Repair if necessary; After stopping the engine, remove the dipstick to verify the oil level is within the standard range.
