Why does the RPM increase after changing the engine oil?

[MaddoxLee]

Here are the reasons for the increased RPM after changing the engine oil and related information about engine oil: 1. Reasons for increased RPM: (1) Different oil used: The car previously used winter oil, which has higher viscosity. This time, all-season oil with lower viscosity was used, reducing engine resistance and causing the RPM to rise. (2) Fake oil used: It's possible that counterfeit oil was used. Fake oil can cause significant damage to the engine, ranging from accelerated engine aging to complete engine failure. Therefore, always choose a reputable auto maintenance facility for oil changes. 2. Engine oil overview: (1) Functions: Engine oil, or engine lubricant, serves to lubricate and reduce friction, assist in cooling, seal against leaks, prevent rust and corrosion, and provide shock absorption. (2) Composition: Engine oil consists of base oil and additives. Base oil is the main component, determining the fundamental properties of the lubricant, while additives compensate for and improve the base oil's performance shortcomings, providing new characteristics and making them essential components of lubricants.