Regular engine oil changes not only keep your engine running smoothly, but also improve fuel economy by increasing engine efficiency. Most modern fuel-efficient engines are specified with low-viscosity oil. This uses low-viscosity (thinner) oil instead of high-viscosity (thicker) oil, reducing frictional resistance and improving fuel economy. To maximize fuel economy, use low-viscosity oil in engines specified for low-viscosity oil. To maintain engine condition, we recommend changing the oil every 3,000 to 5,000 km. However, even if your mileage is less than 5,000 km, we recommend changing the engine oil approximately every six months. Even if you choose high-performance engine oil, excessive intervals can cause the oil to deteriorate and damage the engine. We also recommend changing the oil filter every other oil change.