any way to test what viscosity of oil is in a car

If the conditions noted above are not corrected immediately and boundary lubrication continues, a failure due to the lack of an oil film can occur within hours. This intermittent contact is called boundary lubrication, and damage starts to occur. However, under certain conditions, such as shock loads, continuous heavy loading, extremely high temperatures and/or critically low (thin) viscosity, lubricants may not remain in their normal hydrodynamic film state.Ī condition begins where there is intermittent contact between the wear surfaces. The benefits of oils with a higher VI are:Ī general increase in viscosity at higher temperatures, which results in lower oil consumption and less wear.Ī reduced viscosity at lower temperatures, which will improve starting and lower fuel consumption.Īnother factor in the measurement of viscosity is the ability of an oil to resist shearing or the 'tearing away of one plane of lubricant from another' during the hydrodynamic lubrication function. The higher the VI of an oil, the less its viscosity is altered by temperature changes. This property is referred to as the oil's viscosity index or VI. Many oils contain an ability to resist changes in viscosity due to a change in temperature. Not all oils respond in the same way to a given change in temperature. Kinematic viscosity is measured in the time it takes for a specific volume of oil to flow through a special device called a capillary tube.

These conditions explain why an oil will flow much more easily in summer at a temperature of 25 degrees C (78 degrees F), than it will flow in winter at minus 25 degrees C (minus 13 degrees F).Īn oil's viscosity is measured most commonly by kinematic viscosity and reported in a unit called the centistoke (cSt). It decreases (thins) with increasing temperature and increases (or thickens) with decreased temperature.

Viscosity is a measure of an oil's resistance to flow. It governs the sealing effect of oils and the rate of oil consumption, as well as determines the ease with which machines may be started or operated under varying temperature conditions, particularly in cold climates.

Viscosity affects heat generation in bearings, cylinders and gear sets related to an oil's internal friction.

Any way to test what viscosity of oil is in a car