18/11/2024
Oil: Recommended Viscosity
Viscosity is resistance to flow, it is represented by two numbers. The lower the number, the lower the viscosity of the oil and the faster the oil will move around the engine.
The first number ends with the letter 'W-', stands for Winter and represents the low temperature viscosity of the oil, it is a measurement that simulates starting a car on a cold winter day.
The second number or the high temperature viscosity is the number after the dash and is related to the viscosity of the oil as it is moving around your engine after the car has warmed up and is at normal engine temperature.
For example for 5W-30, the 5W part describes the viscosity of the oil at low temperatures and the 30 defines the viscosity of the oil at normal engine temperatures.
5W-30 will flow easier than a 10W-30 at start-up temperatures and a 10W-30 will flow easier than a 10W-40 at normal engine operating temperatures.
In the past, it was common for vehicles to require higher viscosity oils such as 20W-50’s. But as engine technology has advanced over the years, the size of engines and pathways in engine that oil flows through have gotten smaller and thinner. This has led over time to motor oil viscosity decreasing – currently 5W-30 and 5W-20 are the most popular grade and 0W-20 is the fastest growing grade. These lower viscosity motor oils are needed to move through the thin engine pathways to protect and clean metal surfaces. Lower viscosity motor oils also result in better fuel economy.
It is better to stay with the recommended oil viscosity even in engines with higher mileage, there are high mileage oils available that cater for higher mileage engines with the recommended viscosity.
Come to TT Auto Centre Limited to change your oil!
