What's the Difference Between Semi-Synthetic and Full Synthetic Engine Oil?
1 Answers
Semi-synthetic and full synthetic engine oils differ in the following aspects: 1. Base Oil: Semi-synthetic oil uses Group III base oil, while full synthetic oil is a blend of Group III, IV, and V base oils. Full synthetic oil is one grade higher in base oil selection than semi-synthetic oil. 2. Replacement Interval: Semi-synthetic oil should be replaced every six months or 7,500 kilometers, whereas full synthetic oil can last for one year or 10,000 kilometers. 3. Temperature Performance: Under the same working conditions, full synthetic oil can protect the engine with lower viscosity. Semi-synthetic oil has relatively higher requirements. 4. Vehicle Suitability: Semi-synthetic oil is economical for small-displacement vehicles with smooth driving. Full synthetic oil can be used in various harsh conditions, offering excellent high and low-temperature resistance. 5. Additives: Full synthetic oil contains higher TBN (Total Base Number) additives, extending oil life and cleaning the engine. Semi-synthetic oil has lower TBN additives, shortening the maintenance cycle and producing sulfurized ash. 6. Engine Protection: Full synthetic oil provides better engine protection and internal cleaning compared to semi-synthetic oil.