Best Oil for Generac Generator (Everything Included)

Generators are essential power backup solutions. As with any machine, regular maintenance is crucial to ensure optimal performance and longevity. One of the most critical aspects of generator maintenance is selecting the right oil.

Generac recommends using SAE 30 oil at above 32°F. And 10W-30 oil for the below 40°F to -10°F. They also recommend using synthetic 5W-30 for all temperatures.

In this blog post, I have listed and reviewed the best SAE 30, 10W-30, and 5W-30 oil for the Generac generator. Additionally, I have included the tips and tricks that you need to follow to keep your generator in optimal performance. You could choose your generator according to your condition. Without further ado, let’s get started.

Oil for Generac Generator – Comparison Table

Best SAE 30 oil
Briggs & Stratton 30W Engine Oil
Briggs & Stratton 30W Engine Oil
  • Volume 1.418 L
  • Advanced 30W Engine Oil
Best 5W-30 oil
Royal Purple 11745 HMX
Royal Purple 11745 HMX
  • Volume: 946 ml
  • 5w-30 synthetic Motor Oil
Best 10W-30 oil
Valvoline - 881165
Valvoline – 881165
  • Volume: 4.73 L 
  • Synthetic SAE 10W-30 engine oil 

Generac generator oil type

The oil type recommended for your Generac generator depends on the specific model, engine type, and the ambient temperature where the generator will be operating. It’s essential to refer to your owner’s manual or consult Generac’s customer support for the most accurate oil recommendation for your generator model.

Here are some general guidelines for oil types commonly used in Generac generators:

  1. SAE 30: This conventional oil is suitable for most Generac generators operating in temperatures above 40°F (4°C). SAE 30 is a single-grade oil and does not provide adequate lubrication in colder climates.
  2. 10W-30: This multi-grade oil is commonly recommended for Generac generators operating in a wide range of temperatures, typically between 0°F (-18°C) and 100°F (38°C). It offers better cold-weather performance than SAE 30 and can be used in both conventional and synthetic forms.
  3. 5W-30: This multi-grade oil is ideal for Generac generators used in colder climates or during winter months, as it provides better low-temperature performance compared to 10W-30. Both synthetic and conventional 5W-30 oils can be used.
  4. Synthetic oils: Synthetic oils, like Mobil 1 Synthetic Motor Oil or AMSOIL Synthetic Small-Engine Oil, can provide better protection and performance across a wide temperature range. They may be more expensive than conventional oils but can offer extended drain intervals and enhanced engine protection.

Importance of using the right oil for Generac generators

Selecting the appropriate oil for your Generac generator is crucial for several reasons. let’s have a brief look.

  • Enhancing engine efficiency: The right oil reduces friction between moving parts, ensuring smooth operation and improved fuel efficiency.
  • Reducing wear and tear: Quality oil creates a protective film between engine components, minimizing wear and tear.
  • Extending the lifespan of the generator: Regularly using the recommended oil can prolong the life of your generator, providing reliable power for years to come.
  • Ensuring optimal performance during emergencies: When a power outage occurs, a well-maintained generator with the proper oil can deliver power without any hiccups.
generac generator oil

Factors to consider when choosing oil for your Generac generator

  • Generator model: Generac offers both portable and standby generators. Each type has unique oil requirements based on the engine specifications.
  • Ambient temperature and climate: Your location’s temperature and climate play a significant role in determining the ideal oil viscosity for your generator. Some oils perform better in extreme temperatures, while others are more suitable for moderate climates.
  • Generator usage frequency and duration: If you use your generator frequently or for extended periods, consider using oil with higher performance capabilities.
  • Manufacturer’s recommendations and warranty considerations: Always follow the manufacturer’s guidelines and warranty requirements to avoid voiding your warranty.

SAE 30 oil for Generac Generator

Briggs & Stratton 30W Engine (best synthetic engine oil for Generac)

If you live in an area where the temperature is above 32°F, I will recommend using this Briggs & Stratton 30W Engine Oil. Don’t think about the performance of this oil. No doubt this one is one of the best-performing synthetic engine oil in the market.

This is a bottle of 48 fluid ounces. Comparing the price, this one is worth it indeed. Most importantly, this oil is not only manufactured for Briggs & Stratton generators. You could use this one for Generac smoothly.

Valvoline SAE 30 engine oil

Valvoline is one of the market’s best conventional SAE 30 engine oil. If you are comfortable with the traditional type of oil, I recommend using this engine oil for your Generac generator.

This is a 946 mL quality plastic bottle. And this one is cheaper also.

This quality SAE 30 engine oil protects your engine from deposit formation. It comes with anti-wear additives with advanced technology to ensure the best performance. If you are looking for something inexpensive but worthy, you could try this one.

5W-30 oil for Generac Generator

Royal Purple 11745 HMX SAE 5W-30

If you are looking for high-mileage engine oil for your generator, you could consider this Royal Purple 11745 HMX SAE 5W-30. This one is a stand-out 5W-30 engine oil indeed.

This is a package of 192 fluid ounces. Also, they offer 32 fluid-ounce bottles. So, you could buy any package from the listing.

Royal Purple ensures high engine performance. It protects the generator engine from LSPI. Additionally, this is synthetic oil and comes with additive and advanced technology.

Pennzoil 550022689

Pennzoil 550022689 is another popular and high-performance full synthetic oil for Generac generators in the market. If you are from a varieties temperature regions, you could use this Pennzoil 550022689. Generac recommends using the 5W-30 viscosity for the people like you.

Although this Pennzoil 550022689 was designed for a car, you could use it for your Generac generator. With this Pennzoil 550022689, you will get maximum performance even with your old Generator. This one is cleaner and comes with advanced technology to maximize engine performance and save money.

SAE 10W-30 for Generac Generator

Generac recommends using the 10W-30 oil for people living in areas where the temperature is below 40°F and down to -10°F. Here is the best Performing SAE 10W-30 for Generac Generator.

Valvoline – 881165

This one is one of the most popular SAE 10W-30 oil for the Generac generator. This 10W-30 oil is perfect for a Generac generator and standout for all types of motors.

This is a 5QT bottle, and it is equivalent to 4.73 Liter. This Valvoline engine oil is specially designed for the gasoline engine. You will get 40% more wearer protection than the industry standard oil.

So, if you are looking for the best deal on a moderate budget, consider this standout oil for your generator.

Royal Purple 01130

I prefer Royal Purple for its outstanding performance. This one comes with a moderate price, and the performance is standout. If you never use Royal Purple for any type of motor, you should make it a try. I believe you will feel good.

This Royal Purple 01130 API-Licensed SAE 10W-30 will increase the fuel efficiency of your Generac generator. Also, it increases wear protection and keeps your engine well for a more extended period.

How to change the oil in your Generac generator?

A general rule of thumb is to change the oil after the first 20-30 hours of operation and then every 100 hours thereafter. However, don’t forget to read the manual for the specific models for your Generac generator.

Necessary tools and equipment: You’ll need a wrench, oil drain pan, funnel, new oil, and potentially a new oil filter. here is the step-by-step guideline to change the Generac generator oil.

  1. Turn off the generator and allow it to cool down.
  2. Place the oil drain pan beneath the oil drain plug.
  3. Remove the drain plug with a wrench and let the oil drain into the pan.
  4. If applicable, remove the old oil filter and replace it with a new one.
  5. Replace the drain plug, ensuring it’s tightly secured.
  6. Locate the oil fill cap or dipstick and remove it.
  7. Using a funnel, carefully pour the new oil into the engine, following the manufacturer’s recommended oil capacity.
  8. Replace the oil fill cap or dipstick, ensuring a tight seal.
  9. Wipe away any spilled oil and dispose of the used oil properly, according to local regulations.
  10. Start the generator and let it run for a few minutes to circulate the new oil. Check for any leaks and verify the oil level is correct.

Tips for maintaining optimal performance of your Generac generator

  • Regularly checking oil levels: Check the oil level before each use to ensure it’s within the recommended range. Top off as necessary.
  • Inspecting and replacing air filters: Clean or replace air filters according to the manufacturer’s recommendations to maintain proper airflow and engine performance.
  • Ensuring proper fuel storage and usage: Use fresh, stabilized fuel and store it in an approved container. Replace fuel that’s been stored for longer than three months.
  • Staying up to date with scheduled maintenance: Follow the manufacturer’s maintenance schedule, including oil changes, spark plug replacements, and other essential tasks.


How frequently should I change the oil for my Generac generator?

For the first operation, you should change the oil after 20-30 hours of running. Then you should change the oil every 100 hours of run time. This is the recommendation from Generac.

Can I use 5W-30 in my Generac generator?

While it’s always best to follow the manufacturer’s recommendations for oil type and viscosity, using 5W-30 instead of 10W-30 in your Generac generator may be acceptable in certain situations. Both 5W-30 and 10W-30 are multi-grade oils, with the main difference being their cold-weather performance.

5W-30 oil is designed to flow better at lower temperatures, making it more suitable for colder climates. If you live in an area with colder temperatures or plan to use your generator during winter months, using 5W-30 oil might be a reasonable choice.

However, keep in mind that deviating from the manufacturer’s recommended oil type may have an impact on your generator’s performance and potentially void its warranty. Before making any changes, it’s essential to consult your generator’s owner’s manual or contact Generac customer support for specific guidance on your particular model.

How much oil does a Generac generator take?

The amount of oil required for a Generac generator varies depending on the specific model and engine size. To find the exact oil capacity for your generator, consult the owner’s manual or contact Generac customer support with your model number.

Here are some general oil capacity guidelines for common Generac generator types:

  1. Portable generators: Most portable Generac generators require between 16 to 48 ounces (0.5 to 1.5 quarts) of oil. Smaller models typically need less oil, while larger ones may require more.
  2. Standby generators (air-cooled): Generac air-cooled standby generators usually have an oil capacity of approximately 1.5 to 2.2 quarts (48 to 70 ounces), depending on the model.
  3. Standby generators (liquid-cooled): Liquid-cooled standby generators have larger engines and require more oil. Their oil capacity typically ranges from 4 to 6 quarts (128 to 192 ounces), but it can vary depending on the engine size and model.

Final Thoughts

Choosing the best oil for your Generac generator is vital for optimal performance, efficiency, and longevity. Always follow the manufacturer’s guidelines and maintenance schedules to ensure your generator stays in top shape and is ready to provide reliable power whenever it’s needed. By carefully selecting the right oil and maintaining your generator, you’ll enjoy peace of mind knowing you’re prepared for any power outage or emergency situation.

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Rayan is an engineer, lives in a farmhouse. He has a passion for electronics and alternative energy. He loves to share his thoughts with other people. That is why he started the blog.

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