What is the difference between semi-synthetic oil and fully synthetic oil?

[VanErin]

The differences between semi-synthetic oil and fully synthetic oil are: 1. Different base oils: Semi-synthetic oil uses Group III base oil; fully synthetic oil is a mixture of Group III, IV, and V base oils. 2. Different replacement intervals: Semi-synthetic oil should be replaced every six months or 7,500 kilometers during use; fully synthetic oil should be replaced every year or 10,000 kilometers during use. Engine oil, also known as engine lubricant, serves to lubricate and reduce friction, assist in cooling, seal against leaks, prevent rust and corrosion, and act as a shock absorber in the engine. It is often referred to as the 'blood' of a car. The engine operates at high temperatures internally, with the cylinders cooled by the cooling system. However, certain internal components cannot rely on the cooling system and can only dissipate heat through the circulation of engine oil.