Engine Oil - What's The Big Deal?

Motor Oil - What's The Big Deal?

by Erik Auberg

​What is motor oil, anyway?

​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 improvers. Motor oil is used for the lubrication of internal combustion engines. Basically, motor oil lubricates the moving parts of your engine to reduce friction and wear.

​So I just have to make sure there is oil in my engine, right?

​Not exactly. In order for your vehicle to remain in proper working order, you must change the oil in your engine periodically. How often you need to do this is dependent upon several factors. If you use conventional oil in a gasoline engine, for example, you should change your oil every 3,000 miles or every 3 months, whichever comes first. If you use fully synthetic oil, it can be stretched to somewhere between 5,000-10,000 miles, although pushing the limits can be risky.

​Whoa Whoa Whoa... conventional? Fully Synthetic? What does that mean?

​Conventional oil is made using fossil fuels and is not as good for the environment. Synthetic oil is made up of artificial lubricants with more added detergents for your engine. Additionally, conventional oil breaks down more quickly than synthetic oil. However, some vehicle manufacturers specify to only use conventional or synthetic oil for their vehicles, so make sure to check with your local auto parts store or mechanic before deciding on which oil to use for your vehicle.

​

​

​Okay, so I know my car needs synthetic oil. So I just need to ask for a bottle of synthetic oil, right?

​Well, no. You're on the right track, though!

​

​Every engine has a specific capacity of oil and a specified weight. Some may require 5 quarts of 5w-20 or 9 quarts of 10w-40. It all depends on what you drive!

​Say what?

​The weight of the oil is an assigned classification to describe how viscous (thick) it is.

​Manufacturers have a specified oil weight to be used in their vehicles to make them run most efficiently. Additionally, there may even be a range of weights that you can use for a vehicle based on the temperature the vehicle is being driven in.​

​

The Society of Automotive Engineers (SAE) assigns a viscosity number, or weight, to oil based on its flow at 210 degrees F, which is roughly the standard operating temperature for most motors. The higher the number, the thicker or slower flowing it is, which changes the nature of how it coats internal engine components and protects against heat and friction. This means a 30 weight oil flows more quickly than 50 weight oil, but doesn’t offer quite the same level of protection at higher operating temperatures or in stressful conditions.

​

​

​continued...

​You’ve probably noticed that most bottles of oil actually have two numbers on them, separated by a “w.” These are called multigrade oils, and they are unique in that they have been engineered to offer not just one, but two weights.

Confused? Here’s how it breaks down. The “w” stands for winter and indicates that the lubricant in question has a different viscosity, or different flow characteristics, based on temperature. For example, a 5w30 oil weight rating means that on cold start-up — even at subzero temperatures — the oil flows like a 5 weight oil. However, once warmed up to 210 degrees F, it functions as a 30 weight oil. This is accomplished through the inclusion of unique additives in the mixture.

​Why would you want a thinner oil that acts like a thicker oil once warmed up?

​ If you used a straight oil weight of 30, then the lubricant would be too thick to shoot quickly through the engine when starting on a cold day, which means it would fail to properly protect crucial parts from damage. At the same time, you wouldn’t want to run a straight 5 weight oil either, because it would be too thin to keep a warm engine safe. A multigrade is truly the best of both worlds.

​So what you're saying is, I need to make sure that I buy the correct oil and the correct amount of that oil for my vehicle to keep it properly lubricated. Additionally, I should make sure to change my oil at regular appropriate intervals?

​Here are some questions about the information you just learned

Multiple Choice

What does the "w" in oil's weight mean?

• Weight

• Winter

• Wumbo

• Wallaby

Multiple Choice

What is the standard operating temperature for most engines? This number is the basis of oil weight classification.

• 32 Degrees Fahrenheit

• 100 Degrees Fahrenheit

• 500 Degrees Fahrenheit

• 210 Degrees Fahrenheit

Multiple Select

What are the two main types of motor oil?

• Synthetic

• Claustrophobic

• Brown

• Conventional

Multiple Select

What could happen if you fail to change your vehicle's oil regularly?

• Engine seizure

• Sludge in your engine

• You'll make your mechanic cry uncontrollably

• You'll end up spending a lot more money on repairs of your vehicle

• All of the above.

Open Ended

What is something that we may not have gone over that you would like to know?