The viscosity grade printed on an engine oil bottle, such as 5W-30 or 10W-40, tells you how thick the oil is at two temperatures. Choosing the grade your engine was designed for is the single most important step in choosing an engine oil.
What the two numbers mean
The first number with the W (for winter) describes how the oil behaves when the engine is cold. A lower number means the oil flows faster at start-up, reaching moving parts sooner.
The second number describes how thick the oil stays at normal operating temperature, around 100 °C. A higher number means a thicker oil film when the engine is hot.
Choosing between the three EVShield grades
- 5W-30 fully synthetic suits modern engines, including turbocharged engines, built with tight tolerances. EVShield 5W-30 meets API SP and ILSAC GF-6.
- 10W-30 semi synthetic suits cars driven mostly in town, with frequent stop-and-go traffic. EVShield 10W-30 meets API SN/CJ-4.
- 10W-40 semi synthetic gives a thicker hot film and is widely used in Japanese, Korean and Malaysian cars. EVShield 10W-40 meets API SP.
Check the specification too
Viscosity is only half of the label. The API or ILSAC specification, such as API SP, shows the performance standard the oil meets. Use an oil that meets the specification listed in your owner’s manual or a newer one.
Not sure which grade fits your vehicles or fleet? Send us an enquiry with the make, model and year, and we will recommend a grade.