The difference between 5w-20 and 5w-30 oil is that 5w-30 oil has a higher viscosity at its operating temperature. Viscosity is the term used to describe the thickness of a substance, in this case oil, where a higher number indicates a thicker oil.Continue Reading
Oil viscosity varies inversely with temperature. This means that as the temperature goes up, the thickness (viscosity) of the oil decreases. To use this knowledge in an automotive application, it is important for an oil to be thin enough to spread quickly when a cold engine is started, yet it should not become too thin once the engine reaches its operating temperature. An oil with the rating of 5w-30 is a multiweight oil that will act like a 5-weight oil, which is very thin at cold temperatures, while maintaining the thickness of a 30-weight oil once the engine reaches its operating temperature. This protects the engine from wear at both temperature extremes.
The invention of the modern multiweight oil is made possible by the addition of polymers, which coil up at cold temperatures and mimic shorter molecular chains with a lower viscosity. As the oil's temperature rises, these polymer chains begin to unwind, increasing the effective length of the molecular chain and thereby increasing the viscosity.Learn more about Engine Oil
Choosing the correct motor oil for an automobile depends on many factors, including the age of the vehicle, the weather conditions and climate the vehicle is in, and recommended oil viscosity. Most automobile manufacturers suggest a certain viscosity in the automobile's owner's manual.Full Answer >
The different specifications of oil, or viscosity, refer to the resistance of the oil to flow, and the higher the number, the slower the oil flows. Motor oil comes in two main types, SAE or winter grades, which have the letter "W" on the bottle.Full Answer >
For the 2005 model year, Chrysler recommends that Crossfire owners use engine oil with a 0W-40 viscosity grade. The company further recommends that owners use oil that meets Daimler's MB 229.3 or 229.5 specifications, such as Mobil 1 oil. Chrysler recommends a Mopar 5102905AA oil filter.Full Answer >
The recommended engine oil for a 2010 Audi A4 2.0 engine is SAE 5W40 viscosity oil. If SAE 5W40 is not available, SAE 5W-30 or SAE 0W-40 may be used instead.Full Answer >