What does 15w40 on engine oil mean?
1 Answers
Engine oil 15w-40 refers to the viscosity of the oil. Here is relevant information: 1. It indicates that the applicable temperature range is from -20 degrees to +40 degrees. The 'w' stands for winter-grade oil. The smaller the number before 'w', the lower the ambient temperature it can be used in. The number after the hyphen represents the ambient temperature for non-winter use, with larger numbers indicating higher applicable ambient temperatures. 2. Engine oil, also known as motor lubricant, serves functions such as lubrication and wear reduction, auxiliary cooling, sealing and leak prevention, rust and corrosion protection, as well as shock absorption. Engine oil consists of base oil and additives. The base oil is the main component of lubricants, determining their fundamental properties, while additives compensate for and improve any deficiencies in the base oil's performance, granting it new characteristics.