Engine oil is critical to the health and longevity of your lawn mower.
Whether you’re using a riding mower, a self-propelled mower, or a push mower, you will need to change the oil regularly.
Like cars, lawn mower engines have moving parts that work together at extremely high speeds and temperatures.
Hence, they need sufficient oil levels to run smoothly and not overheat. What if you run out of lawn mower engine oil? Can you use car oil in a lawn mower instead?
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What Kind of Oil Should You Use in Lawn Mowers?
There are many oil brands and types to choose from, but your first consideration should be what works best for your mower.
The type of oil you should use depends on your lawn mower’s engine.
For Two-Cycle Engines
You should know that two-cycle engines require a different oiling process than four-cycle engines.
The former has one tank that holds a premix of oil and gas. It usually comes in a lightweight synthetic blend often labeled as “performance” oil.
It is best to check the owner’s manual to see the recommended two-cycle engine oil for your mower.
For Four-Cycle Engines
Meanwhile, lawn mowers with four-cycle engines have separate oil tanks. The standard oil for these mowers is grade SAE 30.
It comes in three types: conventional, fully synthetic, and synthetic blends, and each of these types have pros and cons.
The correct type of oil to use largely depends on the equipment you are using and the weather in your area.
Let’s discuss in detail the three types of oil used for lawn mower engines:
Conventional Oils
These are mineral-based products refined from crude oil.
The greatest advantage of conventional oils is their cost, which is usually half the price of synthetic oils. They are also widely available.
If you have an old lawn mower, it will highly benefit from conventional oil, as older engine models are not built for synthetic oils.
Fully Synthetic Oils
As the name suggests, synthetic oil is created and developed in a laboratory using petrochemicals that resemble crude oil.
Synthetic oils are used in engines and equipment, including high-performance automobiles and lawn mowers.
Synthetic Blends
The main difference between a fully synthetic oil and a synthetic blend is the quality of the oil used in the product.
Blends normally contain additives to enhance their performance against extreme temperatures.
Lawn Mower Oil Options To Use
One of the key factors to keep in mind when choosing lawn mower oil is the climate in your area. The three common types of oils for mowers are:
SAE 30
This is the most common engine oil used in small engines like those in lawn mowers.
SAE 30 is a monograde oil suitable for warmer temperature ranges, although it may increase oil consumption in temperatures 80 degrees Fahrenheit and higher.
Since it doesn’t have good cold flow properties, use it only in spring, summer, or autumn.
SAE 10W-30
This is a high-viscosity, multi-grade oil suitable for colder temperatures. Viscosity refers to how easily oil pours at a certain temperature.
Use SAE 10W-30 on your lawn mower engine if you live in cooler regions.
SAE 5W-30
This oil is less viscous (thick) at very low temperatures than 10W30, making it suitable for extreme weather conditions. Use it if you live in very cold regions.
Can You Use Car Oil in a Lawn Mower?
Lawn mower engines are similar to car engines in many ways. Hence, you can use car oil if you are in a pinch and need to change or add oil to your mower.
Some types of car oil are suitable for four-stroke lawn mower engines. However, you cannot use car oil for two-stroke engines.
Any two-stroke oil made for air-cooled engines, such as those in water pumps and weed eaters, may work perfectly in your two-stroke mower.
While small engines use the same oil as automobiles, double-check the label first. These products normally have special additives that could harm the engine over time.
If you decide to use car oil in your mower, you must ensure that you use the correct oil.
Automotive motor oils come in multiple grades, so read the instructions specific to your lawn mower model and brand.
What Happens if You Use Car Oil in Your Lawn Mower?
While you can use car oil in your lawn mower’s engine, you must choose a high-quality automotive oil.
If you do so, there is a good chance nothing significant will happen to your machine, especially if you use it sparingly.
However, if you use low-quality motor oil and do not change or replace it for long periods, your lawn mower’s engine might suffer.
In the worst-case scenario, the engine might become inefficient.
As a rule of thumb, you must use high-quality oil that is rated for use in your specific engine.
Moreover, it is best to choose something that contains additives to help grip the grass and protect the engine from rusting.
One good option is synthetic car-engine oil that has lubricating properties.
What Car Oil Can You Use for a Lawn Mower?
It is fine to use synthetic oil in your mower since it is specially designed for engines.
Moreover, synthetic oils have additives that create a protective barrier around the metals in the engine.
They also have lubricating properties to keep your equipment running smoothly all year round.
You will also notice that synthetic oils already have a suitable viscosity to help keep the piston rings of your mower from being overworked.
In comparison, mineral oils usually contain sulfur that accumulates in the carburetor, leading to the deterioration of the metal components of your mower’s engine.
Using SAE 5W-30 or SAE 10W-30 Oil
You can safely use synthetic SAE 5W-30 motor oil in your lawn mower. This oil has a viscosity rating of five, which means it is quite thin and ideal for small engines.
If what you have is 10W30, then it’s okay, too. 5W30 and 10W30 are almost the same; the only difference is that the latter has a slightly thicker viscosity.
This means that the oil won’t be easy to pump around your mower’s engine, affecting engine efficiency.
You can use 10W30 if your mower is older or has a carburetor or manual choke. These models usually have difficulty starting during cold weather, so they are more likely to need thicker oils.
10W30 oil can work at a wide range of temperatures; thus, it is a better choice for colder weather.
How Often Do You Change Lawn Mower Oil?
You need to change the oil in your lawn mower when you notice it has become dirty or foamy in color. You must also change the oil if your equipment burns oil excessively.
Most mechanics recommend changing the oil every 50 hours to extend its life. If you use your mower more often, you may need to replace the oil more often.
Oil for Lawn Mowers
Can you use car oil in a lawn mower? The answer is yes, but you should only use high-quality synthetic oil.
5W30 and 10W30 are your best options, as they have detergent additives that protect against engine wear and tear.
Also, take note that the use of synthetic oils does not change the recommended oil change intervals.
That said, it would be best to check the owner’s manual to see the recommended types of oil for your specific unit.
