Your engine’s lifeblood—What grade of oil should you use?

No doubt about it, engine oil is important to your lawn mower's life.

In fact, selecting the right oil can prolong the life of your mower engine indefinitely.

But how do you know which oil to choose?

With so many factors to consider, selecting the best oil grade can seem be overwhelming.

Well, fret not, we have got you covered.

Here is what you need to know about selecting the right grade of oil!

Understanding How Oil Grading Works

The Society of Automotive Engineers (SAE) developed a categorization of motor oils in which the viscosity, or thickness, is measured (0W-30, 5W-30, etc).

Viscosity is the fluid’s resistance to flow. Thin fluids have a low viscosity, and fluids that are thick have high viscosity. The oil in a lawn mower’s engine changes in viscosity when it is either heated or cooled. By selecting the right engine oil, you can avoid having to troubleshoot lawn mower issues later.

So what does SAE-0W-30, 5W-30, or 10W-30 even mean?

Here’s how it works. The higher the initial number, the thicker the oil—0 is like water and 10 is like honey.

The “W” stands for winter and represents the viscosity of the oil in cold conditions—meaning it has been tested at very low temperatures such as -30° Fahrenheit and can properly lubricate in that environment.

The number 30 at the end represents how well the oil flows after it has been heated to 212° Fahrenheit or higher.

Hence 0W-30, 5W-30, and 10W-30 all have the same viscosity at 212° Fahrenheit, but at lower temperatures, 0W-30 has the least viscosity and 10W-30 has the highest viscosity.

Check This Out: Having issues with your self-propelled lawn mower?

Know Your Environment

Look, oil behaves differently at various temperatures. The outdoor environment can help determine the correct oil for any lawn mower engine.

Even though lawn mowing normally occurs during the warmer months, lawn mowers can still be used in the cooler months for leaf mulching and/or removal.

Other equipment, such as snow blowers, will solely be used in the winter months, and will certainly have different oil requirements.

What oil grade is right for the temperature?

So, how do I know which oil to select based on the weather in my area?

It’s simple, here is what you need to know:

Use SAE 30: in warmer temperatures of 40° F and higher (5° C and higher)
Use SAE 10W-30: for a varying temperature range between 0 to 100° F (-18 to 38° C); this grade of oil improves cold weather starting but may increase oil consumption at 80° F (27° C) or higher
Use a synthetic oil SAE 5W-30: for very cold temperatures of -20 to as high as 120° F (-30 to 40° C) providing the best protection at all temperatures as well as improved starting with less oil consumption
Use SAE 5W-30: for very cold temperatures of 40° F and below (5° C and below)
For continuous-use: such as commercial lawn cutting or pressure washing, use 15W-50 Oil (temperatures from 20°F to 130°F)

Remember: Change Your Oil Regularly

Oil in a lawn mower needs to be changed regularly to ensure its cleanliness and effectiveness.

It’s simple, most manufacturers recommend changing the oil every 20-50 hours of operation. Part of regular lawn mower maintenance includes changing your engine’s oil.

However, it’s best to refer to the owner’s manual to make the best informed decision. Keeping a log of how many hours the mower has been used will help maintain the proper oil changing regiment.

Pro Tip! Clock how long it takes you to cut the grass once. If it takes you 1 hour, and your manual says to replace the oil every 20 hours. You know that after cutting your lawn 20 times to change the oil.

Oil is Your Engine's Blood

Most people know this, the heart is one of the most important organs in an individual’s body. It acts like a dual-chambered pump that circulates blood and provides the body with oxygen and nutrients it needs to survive.

Needless to say, blood is just as important as the heart; it brings a steady supply of essential food and oxygen to the body’s cells. And engine oil acts like the blood of your lawn mower.

Your Lawn Mower’s Engine is the Heart of the Machine

When looking at a lawn mower engine, one can think of it as the heart. It provides the power to rotate the blades and turn the wheels.

The motor oil one puts in the engine is a lawn mower’s lifeblood, which travels through all parts of the engine, lubricating each component so each can perform its designated task.

Just like the blood that circulates through your body, the cleaner the motor oil is, the better the engine will run.

Choosing the Right Oil

Regularly changing the oil in any mower is essential to its prolonged life.

Since the oil is such a vital component of the internal operations, it needs to be treated like the mower’s life depends on it because it actually does.

When to change the oil, the different types of oil, and the best oil for the mowing environment you are in- are essential to maintaining the heart of your mower.