Table of Contents
What viscosity index is better?
A higher VI is more desirable because it enables the lubricant to provide a more stable lubricating film over a wider temperature range. Some oils may have the right viscosity at certain temperatures but do not quite meet the needs of both ends of the temperature range.
What is viscosity index and why is it important?
It allows for a better comparison of the viscosity behavior of different oils based on temperature. The viscosity index is important in order to ensure, e.g., the best possible lubrication for machinery, as temperature changes occur during operation.
How is engine oil viscosity measured?
The most common method of determining kinematic viscosity in the lab utilizes the capillary tube viscometer (Figure 1). In this method, the oil sample is placed into a glass capillary U-tube and the sample is drawn through the tube using suction until it reaches the start position indicated on the tube’s side.
What do the oil viscosity numbers mean?
The short answer:The numbers represent the viscosity of the oil and the W stands for WINTER. The lower the number, the thinner the oil and the better the oil’s cold temperature/ cold start performance. The number after the W describes how thick the oil is at the engine’s normal operating temperature.
Is higher viscosity index oil better?
Viscosity index diagram The slope of the lubricant with a high VI is more horizontal: the viscosity remains more stable across a wider temperature range. This means a lubricant with a higher viscosity index is more desirable, because it provides a more stable lubricating film over a wider temperature range.
Which oil viscosity is best?
Weather Conditions For very cold weather, a viscosity rating of 5W-30 provides maximum protection. When driving in temperatures running from 0 to 60 degrees Fahrenheit, a rating of 10W-30 offers excellent all around protection. For driving in extremely hot conditions, 20W-50 oil offers the best protection.
Which oil is thicker 5W-30 or 10w30?
10w30 is thicker than 5w30 because it has a higher viscosity in low temperatures. The engine oil will flow slower than 5w30 during the cold season. Thicker or higher viscosity metal oil has a better seal compared to low viscosity oil. Thicker oil offers better lubrication of motor and engine parts.
How do you read viscosity?
The number preceding the W designates the viscosity at a low temperature, and the number following represents viscosity when the engine is hot. For example, a 10W-30 motor oil means the viscosity is at 10W when the engine is cold and 30 when the engine is hot. Low viscosities are good for cold temperatures.
What is the difference between viscosity index and viscosity numbers?
Viscosity rating is a measure of the oil’s resistance to flow or thickness, and is the single most important characteristic of hydraulic oil. The viscosity index number indicates the extent of thickness, or resistance to flow, with temperature changes. As an example: 30W oil flows much faster at higher temperatures.
What happens if I use 10w40 instead of 5W-30?
If you use 10-w-40 instead of 5-w-30 specified by the manufacturer then the viscosity of 10-w-40 used by you will be higher and oil thicker than what is specified during winters. Similarly the oil viscosity will be higher and oil thicker than specified during summers.