Oil is essential for a lawn mover to function properly. In order to keep your oil in good shape, you must change it. Many people wonder if there is a special type of oil made specifically for lawn mowers or can you use car oil in a lawn mower?
In this article I’ll cover some of the basics of changing lawn mower oil. I’ll also answer the question that likely brought you here regarding whether or not you can use car oil in lawn mowers.
This article was last updated on by Lawn Chick Owner Sarah Jameson
Article content reviewed for accuracy by Certified Horticulturist Nicole Forsyth, M.S. and by Horticulturist Arthur Davidson, A.S.
Why Changing the Oil in Your Mower Matters
Although it may not be the most fun task, oil maintenance should be performed regularly. The University of Florida IFAS Extension office describes it as “an essential step in extending the life of your mower.” I agree – in fact, it’s one of the easiest and most important lawn mower maintenance practices you should include in your annual spring maintenance.
In the long run regular oil changes will save you money and avoid a malfunction in your lawn mower. Likewise, changing the oil in your lawn mower is not a difficult task if you know what to do.
Step one in making sure that your oil is doing the most for your lawn mower is making sure that you have the correct type of oil.
An important note about safety – Experts like the Mississippi State University Extension Service advise that you “never touch a hot engine, blades, or other moving parts.” I recommend that you always disconnect or remove the spark plug wire as an added safety precaution before you service your mower. On most mowers this is pressure-fit, and the connection can be broken and reconnected in moments without the use of any specialized tools.
What Type of Oil do I use in my Lawn Mower?
The short answer is yes, you can sometimes use the same oil that you use in your car in your lawn mower.
But before you go forward there are a few things to know first.
Lawn Mower Oil Quality
Lawn mowers generally require a higher-priced oil. A great type of oil to use in most lawn mowers is SAE 30 motor oil. This oil performs best in small engines when outdoor temperatures fall in the 40-100 degree Fahrenheit range, which is what the temperature will be for most people operating a mower.
The SAE rating (which comes from and is named for the Society of Automotive Engineers) is a categorization that indicates the thickness or viscosity of motor oil, and it’s printed clearly on every bottle of motor oil.
Although SAE 30 will generally do the job, I recommend looking at your lawn mowers owner’s manual for specific guidance. It’s important to find the exact oil that will keep your lawn mower running all year long.
I always recommend using the recommended oil for your mower printed in your owner’s manual for best results and to make your mower last.
Always remember when thinking about the oil that you will put into your lawn mower: lawn mowers need higher quality oil. It should be at least SAE 30 to run well.
Your car can handle a lower quality oil and still be fine. So really, whether you can use car oil in your mower is determined by what you put into your car.
If you don’t buy a high-quality oil for your car, I recommend using a different oil for your lawn mower.
When should I change the oil in my lawn mower?
It may come as a surprise to many lawn mower owners, but you should change the oil in your lawn mower about as often as you change the oil in your car.
This is especially true for those who live in drier, dustier climates where particles could easily get into your oil.
My Recommendation
I recommend changing the oil in your lawn mower every other mowing season (minimum). It’s generally worth the time and money to change the oil at the beginning of each year.
I’ve owned my Honda self propelled mower for over ten years now, change the oil annually, and it still starts up on the first pull every spring thanks to regular maintenance.
But really, the number of hours you use your mower should dictate your oil change schedule, rather than any strict guideline on the passage of time.
You’ll find a wide range of recommendations online for how many hours you can go without changing your oil – with most experts recommending somewhere between 25 and 50 hours of run time.
My best advice is that when you buy a new mower, change the oil after the first 5 hours of operation, and after that you should plan to change it every 40 hours or seasonally – whichever comes first.
Of course this is general advice. This could vary based on how often you mow your lawn, the type of mower you have (and how old it is), etc.
- If you see smoke when you’re running your mower it’s time to change the oil.
- If you check the dipstick and it’s dark black and dirty, it’s time to change the oil.
Related: How to Start a Lawn Mower that Has Been Sitting
How do I Change the Oil in my Lawn Mower?
After checking your user manual (if you don’t have it handy, you can usually look it up online) to find out what kind of oil your lawn mower should have and how often you should change the oil in your lawn mower, you are probably wondering, “How do I change the oil in my lawn mower?”
Here are the steps you should take to change the oil in your lawn mower properly.
Steps to Change Lawn Mower Oil
- Empty all of the gasoline from your lawn mower’s fuel tank (optional).
- Disconnect the Spark plug wire (recommended safety measure).
- Look to see if your mower has an oil drain plug.
- If your mower has an oil drain plug, open it to drain out the oil into a pan or container.
- If your mower does not has an oil drain plug, tilt your lawn mower on its side, ensuring the carburetor is on the raised side, and drain out all of the oil from the dipstick hole where you typically add oil. I recommend having a long or flexible funnel for this so you don’t spill.
- Tilt your lawn mower upright and add new, clean oil to your lawn mower.
The Role of Operating Temperature on Oil Type for Mowers
According to Briggs & Stratton, “outdoor temperatures determine the proper oil viscosity for the engine” of most lawn mowers. They go on to suggest that “most outdoor power equipment will operate well with 5W30.”
Here’s a chart you can use for some guidance on what type of oil may be best for your mower or small engine based on outdoor temperature:
| Outdoor Temperature Range | Recommended Oil Type |
|---|---|
| 40-100 degrees Fahrenheit | SAE 30 |
| 0-100 degrees Fahrenheit | 10W30 |
| Anything under 40 degrees Fahrenheit | 5W30 |
| Anything under 100 degrees Fahrenheit | Synthetic 5W30 |
| Anything over 20 degrees Fahrenheit | High Quality Synthetic 15W50 |
While there’s clearly some overlap here, the last three items on the list are what you’ll want to use if you’re operating a small engine in extreme temperatures.
For example if you regularly mow in temperatures over 100 degrees, you may need to upgrade to a high quality synthetic oil like 15W50 rather than using the SAE 30 or 10W30 you’re using now.
Why Buy Specialty Lawn Mower Oil for Your Mower?
One advantage to buying specialty lawn mower oil online or at a hardware or big box store is that the containers are smaller and they are generally sized appropriately so that you’ll add the correct amount of oil and won’t overfill the oil tank of your mower.
This is ideal for most homeowners who plan for an oil change annually, and don’t want to keep a larger bottle sitting around for several years.
Where to Dispose of Used Lawn Mower Oil
After you’ve changed your oil, what do you do with the old, dirty oil you removed from your mower?
Don’t just throw it away!
Many businesses that sell or change motor oil regularly (like auto shops or oil quick-change shops) will accept your oil for recycling free of charge. Advance Auto Parts and AutoZone are two stores that I know will usually accept oil for recycling.
You can also search “used oil recycling near me” on Google to find a local recycling facility that will accept your used mower oil.
