What is the viscosity grade?

Article by: Beatriz Castro | Last update: April 10, 2022
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Viscosity is the resistance to flow of a fluid. Motor oil viscosity grades are based on a scale developed by the American Petroleum Institute (API) lubricants organization.

What does 10W40 and 20W50 mean?

what the numbers mean

The “20W” indicates how fast the engine starts when cold or in cold weather. The “50” refers to the thickness of the oil when the engine has been running for a while. 20W50 motor oil is relatively viscous and thick. Most modern oils are 10W40 or even 5W40.

What is 15w 40?

This W stands for “winter”, and the number indicates the viscosity of the oil at low temperatures. An oil with a low SAE W number will have better fluidity, thus facilitating cold starting and reducing engine wear.

What is ISO viscosity grade?

A number indicating the nominal viscosity of an industrial lubricating fluid at 40°C (104°F) as defined in ASTM D-2422 for the Viscosity Standard System for Industrial Lubricating Fluids. Essentially the same as the ISO 3448 standard.

What does SAE 10w 50 mean?

Motorcycle oils that contain a 10w50 nomenclature, this determines the lubricity range, in this case for you to understand better, the number 10 is its cold level, for this reason the letter W (Winter or winter), this guarantees a clean start and bold.

22 related questions found

What is SAE 10 oil?

Description Lubricant oil specially formulated to meet the requirements of the CATERPILLAR, ALLISON and KOMATSU specifications, applicable in servo transmissions, clutches and brakes, as well as in final drives, gears and differentials (according to SAE grade).

What is the SAE in the oil?

For its part, the SAE (Society of Automotive Engineers) index standardizes viscosities and interprets them on a scale of SAE degrees. The API classifies motor lubricating oils with two initial letters: “S” for Gasoline engines and “C” for Diesel engines.

What is ISO and SAE?

Normally we speak of ISO viscosity for industrial oils and SAE viscosity for automotive oils.

What does ISO220 mean?

ISO VG 220 is equivalent to SAE 90 for gears. ISO VG 460 is equivalent to SAE 140 for gears. To measure the viscosity of an oil under conditions very different from those in which it was tested, to determine the SAE or ISO grade, you can use a viscometer.

What does ISO46 mean?

ISO 46 Hydraulic Oil is an exceptional quality, high performance hydraulic oil developed to meet the needs of environmentally acceptable hydraulic fluids. This product is based on easily biodegradable synthetic esters.

When to use 15W 40 oil?

The 15W40 lubricating oil is precisely designed to protect the diesel engine of trucks, trailers and tractors, since it supports the differences in operation between a car and these vehicles.

What motors use 15W 40?

15w40 – See product

It is a mineral oil that is used in both cases, for diesel and gasoline vehicles, and with a range between -10ºC and 40ºC. Recommended for no more than 5 thousand kilometers.

When is 15W40 oil used?


As a 15W-40 viscosity grade, it flows like a 15 viscosity oil from winter start-up; however, it provides anti-wear protection 40 once the engine reaches full operating temperature.

What happens if I mix 10w40 and 20w50 oil?

I must not mix oils

It is not recommended to do it, except in an emergency, since it will end up losing viscosity and additives, which will result in poor engine lubrication.

When is 20W50 oil used?

A 20W-50 motor oil is often used in older cars or in especially hot climates. Castrol GTX 20W-50 has been specially formulated to extend the life of your engine by keeping it free of sludge, even in extremely high temperatures.

What does 10w40 in motor oil mean?

The number before W represents the winter viscosity grade. In other words, the ability of the engine to start, even at low temperatures. The lower the number, the easier it is for the engine to start from cold.

Where is an ISO 220 oil applied?

This oil is recommended for the lubrication of gearboxes (oil bath, oil vapor or oil circulation lubrication) and is especially suitable for heavy loads and high temperatures.

What does the term ISO 32 mean?

Bases are usually named by their viscosity, an ISO 32 (International Standards Organization) grade means an oil with a viscosity of 32 cSt (at 40 ºC), while an ISO 15 has a viscosity of 15 cSt at the same temperature.

What does ISO VG 68 mean?

VG stands for Viscosity Grade, and indicates the viscosity in centistokes (cSt) of the oil at 40°C for refrigerant oils.

What is the ISO VG standard?

This proposal is known as the International Organization for Standardization Viscosity Grade, abbreviated as ISO VG. You don’t have to be in this field long to hear someone say that viscosity is the most important physical property of a fluid when determining lubrication requirements.

What does an SAE 40 oil mean?

Once the engine is started and warmed up, the oil works as SAE 40 grade, that is; the viscosity with which the engine is protected most of the time. Higher numbers mean better high temperature performance.

What is the difference between 15W40 and 20W50 oil?

The 15W40 is recommended for engines with power requirements and moderate demand. The 20W50 is specially designed for high mileage vehicles that by design require a lubricant with a higher viscosity index.

What does SAE 20w 50 mean?

These are the temperatures at which the oil will have the optimal viscosity and performance to work inside your car. So the 20w-50 means that the correct minimum operating ambient temperature for this oil will be 20°C and the maximum 50°C.

What is SAE viscosity?

Viscosity is defined as the internal resistance that opposes any fluid to flow under the action of an external force, understood as gravity or shear stress.

When to use 15w50 oil?

Applications. Mobil 1 15W-50 is recommended for all types of vehicles, being suitable for high performance turbocharged and supercharged multi-valve and fuel injected gasoline and diesel engines used in passenger cars, vans and light trucks.

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