Is Thinner or Thicker Engine Oil Better?

[DiCaleb]

There is no absolute good or bad; the appropriate engine oil grade should be selected based on the vehicle model and season. Under the premise of ensuring lubrication, thinner viscosity offers better fluidity and lower resistance, while thicker viscosity results in poorer fluidity and higher resistance but provides relatively greater stability. Below are relevant details: 1. Engine Oil Selection: Generally, due to the widespread use of turbocharged engines in German cars and their technical structures, they require higher viscosity oil. In contrast, Japanese cars, with their different engine design philosophies, recommend low-viscosity, high-fluidity oil. Additionally, thicker oil provides better protection in summer, while thinner oil facilitates easier starts in winter. 2. Hazards of Incorrect Oil Viscosity: If the replaced oil viscosity is unsuitable, overly thin oil can lead to excessively low oil pressure, insufficient lubrication, increased friction between engine parts, resulting in abnormal noises and accelerated wear. If the oil is too thick, excessive resistance increases engine load, thereby raising fuel consumption. Therefore, it is best to choose the appropriate oil type and viscosity according to the vehicle model's requirements.