Grades of motor oil

SAEs J300 standard first published in 1911 and revised numerous times since classifies oil into 11 viscosity grades0W 5W 10W 15W 20W 25W 20 30 40 50 and 60. With those factors in mind lets talk about engine oil differences.

The American Petroleum Institute API is the only national trade association that represents all aspects of Americas oil and natural gas industry.

Grades of motor oil. Motor Oil Grades 0W-20 This engine oil is relatively thinner when you start the engine. Here in 0W-20 the viscosity of the oil is 0 when. 0W-30 The 0W-30 oil is engineered to behave as a 0 weight oil at the starting temperature and a 30 weight oil when the.

0W-40 The 0W-40 oil is engineered to. The difference in the viscosity is the reason you see multiple numbers on grades such as 5W-30. The number preceding the W is a measurement of the oils flow at 0 degrees Fahrenheit.

The lower the first number is the better the oil flows at below freezing temperatures. So 0W-30 would be a better cold-weather lubricant than 5W-30. SAEs J300 standard first published in 1911 and revised numerous times since classifies oil into 11 viscosity grades0W 5W 10W 15W 20W 25W 20 30 40 50 and 60.

The W signifies winter not weight. Oils first received this W designation from SAE in the 1950s. There are many different grades of motor oil available each designed for certain operating conditions.

Some common grades that you might be familiar with include 5W-40 5W-30 10W-30 10W-40 15W-40 and 20W-50. There are also multi-grade oils that are for use in vintage or antique engines. Monograde oils such as SAE 30 40 or 50 are no longer used in latest automotive engines but may be required for use in some vintage and antique engines.

Straight SAE 30 oil is often specified for small air-cooled engines in lawnmowers garden tractors portable generators and gas-powered chain saws. Motor oil engine oil or engine lubricant is any one of various substances that consist of base oils enhanced with various additives particularly antiwear additives detergents dispersants and for multi-grade oils viscosity index improversMotor oil is used for lubrication of internal combustion enginesThe main function of motor oil is to reduce friction and wear on moving parts and to. Motor oil becomes thinner and runnier as it heats up and thickens as it cools.

Within reason thicker oil generally maintains a better film of lubrication between moving parts and seals vital. Consequently if the motor oil performs like a SAE 20 motor oil at the reduced temperatures the scale varies - see the chart then it will be a SAE 20W motor oil. If a motor oil passes the cold temperature or W winter grade specification for a SAE 15W and at 210 F 100 C flows through the viscometer like a SAE 40 motor oil then the label will read 15W-40.

The Society of Automotive Engineers SAE defines a numerical system for grading motor oils according to viscosity. The suffixes 0 5 10 15 and 25 followed by the letter W designate the engine oils winter grade. Look to your owners manual.

It specifies the viscosity grade required for your cars engine. The American Petroleum Institute API is the only national trade association that represents all aspects of Americas oil and natural gas industry. Our more than 600 corporate members from the largest major oil company to the smallest of independents come from all segments of the industry.

The 30 reflects the viscosity grade of the oil when the engine temperature is at 212 F. If you live in a colder environment a 5W rating oil will be able to start your engine a lot sooner than a 10W rated oil. Some vehicle manufacturers provide a range of recommended motor oil viscosity grades based on the outside temperature in which the car is driven.

Other manufacturers recommend the use of only one motor oil viscosity grade. For best engine performance always follow the manufacturers recommendations found in your vehicles owners manual. With those factors in mind lets talk about engine oil differences.

The main difference between basic oils is their viscosity grades. Dont let the word overwhelm you it is really quite simple. Viscosity is a measurement of how quickly the oil flows through your engine.

Since thicker or higher viscosity oils take longer to flow it makes. To take care of your engine drive in the warmer months it is best to choose a motor oil with a high viscosity grade that is not marked W meaning SAE 8 12 16 20 30 40 50 or 60 motor oils. The composition of engine oil is always evolving as new discoveries are made so the defined classifications follow suit with the evolution of oil quality.

The American Petroleum Institute API defines specifications for engine oils such as SG or SE. Engine oil manufacturers in turn label containers with the oil rating. We carry top motor oil brands such as Mobil Castrol Valvoline Pennzoil as well as our own OReilly-branded oil.

You can find your preferred conventional synthetic high-mileage diesel or heavy-duty engine oil at your local OReilly. SAE viscosity grades are divided into two distinct groups. There are the Wwinter grades of engine oil and the straight high temperature viscosity grades the non-W viscosity grades.

The Wwinter viscosity grades describe the oils viscosity under cold temperature engine starting conditions. 5W-30 and 5W-40 are 2 common types of engine oil that you might come across. The 5 refers to the viscosity in cold weather and the W stands for winter.

The 30 or 40 refers to the oil flow at higher engine temperatures. 30 is often for newer petrol engines while 40 is often for older or diesel engines.