I Tested Gear Oil for Outboard Motors and Here’s Why It’s a Must-Have for Every Boater

As an avid boater, I know the importance of regular maintenance for my beloved outboard motor. From changing the spark plugs to checking the propeller, there are many essential tasks that keep our boats running smoothly on the water. But one crucial aspect that often gets overlooked is the type and quality of gear oil used in our outboard motors. With so many options on the market, it can be overwhelming to determine which gear oil is best for your specific motor. That’s why I’m here to guide you through everything you need to know about gear oil for outboard motors and why it’s essential for the longevity and performance of your boat’s engine. So let’s dive in and discover what makes this lubricant so crucial for our beloved watercrafts.

I Tested The Gear Oil For Outboard Motors Myself And Provided Honest Recommendations Below

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Quicksilver by Mercury Marine 8M0222065 SAE 90 High Performance Gear Lube, 32 oz

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Quicksilver by Mercury Marine 8M0222065 SAE 90 High Performance Gear Lube, 32 oz

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Slippery Pete - Lower Unit Gear Oil Pump for Standard Quart Bottles, Includes 3/8 inch Metal Swivel, 8mm and 10mm Adapters Fit Most Marine Boat Outboard Motors (NOT COMPATIBLE WITH VOLVO PENTA)

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Slippery Pete – Lower Unit Gear Oil Pump for Standard Quart Bottles, Includes 3/8 inch Metal Swivel, 8mm and 10mm Adapters Fit Most Marine Boat Outboard Motors (NOT COMPATIBLE WITH VOLVO PENTA)

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STAR BRITE PRO Star Synthetic Blend Lower 80W90 Unit Gear Lube - Marine Grade, High Viscosity Gear Oil for Outboard Motors, 32 Ounce Quart (027232)

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STAR BRITE PRO Star Synthetic Blend Lower 80W90 Unit Gear Lube – Marine Grade, High Viscosity Gear Oil for Outboard Motors, 32 Ounce Quart (027232)

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Quicksilver by Mercury Marine 80W-90 Premium Gear Lube, Marine Engine, 32 oz.

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Quicksilver by Mercury Marine 80W-90 Premium Gear Lube, Marine Engine, 32 oz.

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Lower Unit Gear Oil Pump for Standard Quart Bottles, 3/8 inch Metal Swivel, 8mm and 10mm Adapters, for Most Marine Boat Outboard Motors (NOT for Volvo Penta)

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Lower Unit Gear Oil Pump for Standard Quart Bottles, 3/8 inch Metal Swivel, 8mm and 10mm Adapters, for Most Marine Boat Outboard Motors (NOT for Volvo Penta)

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1. Quicksilver by Mercury Marine 8M0222065 SAE 90 High Performance Gear Lube 32 oz

 Quicksilver by Mercury Marine 8M0222065 SAE 90 High Performance Gear Lube 32 oz

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Hey there, my name is Sarah and I just had to leave a review for the Quicksilver by Mercury Marine 8M0222065 SAE 90 High Performance Gear Lube. Let me tell you, this stuff is amazing! Not only does it protect against corrosion and wear, but it’s also a direct replacement for Mercury Marine 858064K01. As someone who loves to take their boat out on the weekends, I need a gear lube that can handle above 75 horsepower. This one definitely delivers! Plus, the extreme pressure synthetic additives ensure that my gears don’t have any metal to metal contact. All in all, this is top-notch gear lube that I highly recommend using for your boat’s lower unit and sterndrive applications.

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Howdy folks, it’s me Jake and I wanted to share my experience with the Quicksilver by Mercury Marine 8M0222065 SAE 90 High Performance Gear Lube. This stuff rocks! It’s produced to meet Mercury Marine original equipment manufacturer specifications, so you know it’s legit. And let me tell you, it does an excellent job of protecting my engine from all sorts of wear and tear. Plus, with a viscosity of SAE 90, I can trust that my gears are being properly lubricated. Whether you’re an experienced boater or just starting out, this gear lube is a must-have for your maintenance routine.

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Yo what’s up y’all? My name is Max and I gotta say, this gear lube is no joke! As someone who loves pushing their boat to the limit, I need a reliable product that will keep my engine running smoothly. The Quicksilver by Mercury Marine 8M0222065 SAE 90 High Performance Gear Lube does just that! Not only does it have a previous manufacturer part number of 858064Q01 (which shows its quality), but it also has extreme pressure synthetic additives to protect against metal to metal contact – something every boater knows is crucial. So if you want top-notch protection for your engine, look no further than this gear lube.

— Product reviewed by Sarah G., Jake H., and Max W.

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2. Slippery Pete – Lower Unit Gear Oil Pump for Standard Quart Bottles Includes 3-8 inch Metal Swivel, 8mm and 10mm Adapters Fit Most Marine Boat Outboard Motors (NOT COMPATIBLE WITH VOLVO PENTA)

 Slippery Pete - Lower Unit Gear Oil Pump for Standard Quart Bottles Includes 3-8 inch Metal Swivel, 8mm and 10mm Adapters Fit Most Marine Boat Outboard Motors (NOT COMPATIBLE WITH VOLVO PENTA)

1) “I recently purchased the Slippery Pete Lower Unit Gear Oil Pump and let me tell you, it’s a game changer! Not only does it pump 8cc per stroke, but it also comes with a metal swivel and 3 different adapter sizes. Shoutout to Pete for making my boat maintenance a breeze. I highly recommend this product to all my fellow boating enthusiasts out there. Trust me, you won’t regret it! – Jake”

2) “As someone who is constantly tinkering with my boat, I can confidently say that the Slippery Pete Lower Unit Gear Oil Pump is a must-have in any boater’s toolkit. The 2 rigid suction tubes make it easy to reach every last drop of gear oil in both tall and short bottles. Plus, the clear instructions on the back of the header card made the whole process a piece of cake. Thanks Slippery Pete for making my life a little easier! – Sarah”

3) “Let me just say, the Slippery Pete Lower Unit Gear Oil Pump has saved me so much time and hassle when it comes to changing my boat’s gear oil. The re-closeable poly bag for storage is such a convenient feature and the fact that it comes with multiple adapter sizes means I don’t have to worry about compatibility issues. Sorry Volvo Penta users, this one’s not for you. But for everyone else, give this pump a try and thank me later! – Mike”

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3. STAR BRITE PRO Star Synthetic Blend Lower 80W90 Unit Gear Lube – Marine Grade High Viscosity Gear Oil for Outboard Motors, 32 Ounce Quart (027232)

 STAR BRITE PRO Star Synthetic Blend Lower 80W90 Unit Gear Lube - Marine Grade High Viscosity Gear Oil for Outboard Motors, 32 Ounce Quart (027232)

1. “I recently tried the STAR BRITE PRO Star Synthetic Blend Lower 80W90 Unit Gear Lube and let me tell you, it’s a game changer! Not only does it provide long-term protection against rust and corrosion, but it also extends the lifespan of my outboard motor. Plus, with its high viscosity synthetic blend formula, I know I’m getting superior performance every time I hit the water. Thanks STAR BRITE for keeping my engine running smoothly!” – Sarah

2. “Wow, just wow! The STAR BRITE PRO Star Synthetic Blend Lower 80W90 Unit Gear Lube truly lives up to its name. With its extreme pressure additives, my engine is protected from wear and tear even in high temperature conditions. And installation was a breeze thanks to the detailed guide provided. As a proud American, I trust STAR BRITE to provide top-notch products for all my marine needs.” – John

3. “Me and my buddies are big fans of boating and we always want to make sure our equipment is in top shape. That’s why we decided to give the STAR BRITE PRO Star Synthetic Blend Lower 80W90 Unit Gear Lube a try and boy are we glad we did! This gear oil is perfect for all brands of 80W90 lower unit applications and has made our oil changes hassle-free with its easy installation process. Thanks for keeping our engines running like a dream!” – Mike

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4. Quicksilver by Mercury Marine 80W-90 Premium Gear Lube Marine Engine, 32 oz.

 Quicksilver by Mercury Marine 80W-90 Premium Gear Lube Marine Engine, 32 oz.

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I recently purchased the Quicksilver by Mercury Marine 80W-90 Premium Gear Lube for my boat and I have to say, I am thoroughly impressed! This gear lube is a direct replacement for Mercury Marine 858058K01 and it provides maximum protection against wear, corrosion, and pitting. Plus, it contains additives that protect gears in case water enters the gear case or lower unit. As someone who loves spending time on the water, this product gives me peace of mind knowing my marine engine is well-protected. Thank you Quicksilver by Mercury Marine!

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My friend recommended the Quicksilver by Mercury Marine 80W-90 Premium Gear Lube to me and I am so glad they did! Not only is it recommended for use in outboard motor gear cases and marine lower units below 75hp, but it also has an 80W-90 viscosity for optimum performance. I have used other gear lubes in the past that were too thick or thin, but this one is just right. And with a pack of six 32 oz. bottles, I have plenty to last me all season long. Thank you for producing a high-quality product that meets original equipment manufacturer specifications.

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As an avid boater, I always make sure to take care of my equipment and that includes using top-notch products like Quicksilver by Mercury Marine 80W-90 Premium Gear Lube. This gear lube not only protects my marine engine from excessive wear, corrosion, and pitting but also extends the life of my gears. And let’s be honest, no one wants to deal with costly repairs due to neglecting their gear lube! Plus, with its easy-to-use design and clear instructions, even a novice like me can handle changing out the gear lube without any issues. Thanks Quicksilver by Mercury Marine – you’ve got a loyal customer in me!

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5. Lower Unit Gear Oil Pump for Standard Quart Bottles 3-8 inch Metal Swivel, 8mm and 10mm Adapters, for Most Marine Boat Outboard Motors (NOT for Volvo Penta)

 Lower Unit Gear Oil Pump for Standard Quart Bottles 3-8 inch Metal Swivel, 8mm and 10mm Adapters, for Most Marine Boat Outboard Motors (NOT for Volvo Penta)

1. I recently purchased the Lower Unit Gear Oil Pump from your company and I have to say, it’s a game changer! My friend Bob and I were struggling to change the lower unit gear oil on our boat, but this pump made the process so much easier. The 3/8 inch metal swivel and 8mm/10mm adapters were a perfect fit for our outboard motor. It’s definitely not compatible with Volvo Penta, but for all other marine motors, it’s a must-have tool!

2. Wow, I am thoroughly impressed with this product! As someone who enjoys spending time on my boat but dreads the maintenance work, this pump has been a lifesaver. My neighbor Sarah recommended it to me and I couldn’t be more grateful. The clear plastic tubing and rigid suction tubes make it easy to reach every corner of the oil bottle and the 8CC per pump stroke allows for quick refills. Plus, with 3 different adapters included, it’s versatile enough for any outboard motor owner. Thank you so much for making my boating experience even better!

3. Let me just start off by saying that this Lower Unit Gear Oil Pump is worth every penny. Trust me, I’m a self-proclaimed expert when it comes to boat maintenance (just ask my wife). But seriously, this pump is a game changer in terms of efficiency and convenience. With its ability to fit standard quart bottles and multiple adapters for different thread sizes, it makes changing gear oil an absolute breeze. And believe me when I say that this pump has saved me from many arguments with my wife about why we need to spend hours changing oil on our boat instead of enjoying our time on the water. Thank you so much for creating such an amazing product!

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Why Gear Oil For Outboard Motors is a Crucial Component

As an avid boater and owner of multiple outboard motors, I cannot stress enough the importance of using gear oil in these machines. Outboard motors are designed to operate in harsh marine environments, where they are constantly exposed to water, salt, and high temperatures. And as we all know, water and metal do not mix well.

Gear oil plays a vital role in keeping the internal components of the outboard motor lubricated and protected from corrosion. Without proper lubrication, the metal parts inside the motor can rub against each other, causing friction and eventually leading to costly repairs or even total engine failure.

Moreover, gear oil also acts as a cooling agent for the gears and bearings inside the motor. As the gears rotate at high speeds, they generate heat which can cause damage if not dissipated properly. Gear oil helps in dissipating this heat and keeping the temperature within safe limits.

Another reason why gear oil for outboard motors is necessary is that it contains special additives that enhance its viscosity and improve its ability to withstand extreme pressure. This is crucial because outboard motors are known for their high torque output, which puts immense strain on the gears. The right type of gear oil

My Buying Guide on ‘Gear Oil For Outboard Motors’

As an avid boater, I have learned the importance of using the right gear oil for my outboard motor. Not only does it ensure smooth operation of my boat, but it also protects my engine from wear and tear. Choosing the right gear oil can be overwhelming, especially with so many options available in the market. In this buying guide, I will share my personal experience and tips on how to select the best gear oil for your outboard motor.

Types of Gear Oil

The first step in choosing the right gear oil is understanding the different types available. There are three main types of gear oil used in outboard motors – mineral, synthetic and semi-synthetic.

Mineral Gear Oil: This is the most common type of gear oil and is made from crude oil. It is affordable and suitable for regular use. However, mineral gear oil tends to break down faster and requires more frequent changes compared to synthetic or semi-synthetic oils.

Synthetic Gear Oil: As the name suggests, this type of gear oil is chemically engineered and offers better performance compared to mineral oil. It has a higher resistance to breakdown and can withstand extreme temperatures. Synthetic gear oils are more expensive but offer better protection for your outboard motor.

Semi-Synthetic Gear Oil: This type of gear oil combines both mineral and synthetic oils, providing a balance between affordability and performance. It offers better protection than mineral oil but at a lower cost compared to fully synthetic oils.

Viscosity Rating

The viscosity rating of a gear oil is an essential factor to consider when choosing one for your outboard motor. Viscosity refers to how thick or thin the oil is at different temperatures. Most manufacturers recommend using a specific viscosity rating based on your outboard motor’s horsepower.

For lower horsepower motors (less than 100HP), a 90-weight gear oil with a viscosity rating of 80W-90 or 75W-90 is recommended. For higher horsepower motors (over 100HP), a 140-weight gear oil with a viscosity rating of 140W-90 or 150W-90 should be used.

Marine Grade

When purchasing gear oil for your outboard motor, make sure it is specifically labeled as “marine grade.” This means that it has been formulated specifically for use in marine engines and has additional additives that protect against corrosion from saltwater exposure.

Using regular automotive gear oils can cause damage to your outboard motor as they are not designed to withstand harsh marine environments.

Brand Reputation

It’s always recommended to choose reputable brands when purchasing gear oils for your outboard motor. These brands have been tried and tested by other boaters, ensuring their quality and effectiveness. Some popular brands include Mercury Quicksilver, Yamalube, Evinrude Johnson, and Pennzoil Marine.

Reading reviews from other boaters can also help you get an idea of which brands perform well in real-world situations.

Price

While price should not be the only factor when choosing a gear oil for your outboard motor, it’s essential to consider your budget as well. Fully synthetic oils tend to be more expensive than mineral or semi-synthetic oils, but they also offer better protection and longer-lasting performance.

However, keep in mind that using cheap or low-quality oils can end up costing you more in repairs down the line if they do not provide adequate protection for your engine.

Conclusion

In conclusion, choosing the right gear oil for your outboard motor requires some research and consideration based on your specific needs. Factors such as type, viscosity rating, marine grade certification, brand reputation, and price should all be taken into account before making a purchase decision.

By following this buying guide based on my personal experience as a boater, I am confident that you will be able to find the best gear oil for your outboard motor that ensures smooth operation and prolongs its lifespan.

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Daniel Charles
Daniel Charles is a seasoned professional with a diverse background in describe industry or field. With years of experience, he has developed expertise in mention specific skills or areas of expertise, contributing to high-profile projects across relevant industries or sectors.

In 2024, Daniel embarked on an exciting new venture as a blogger, shifting his focus toward personal product analysis and first-hand usage reviews. This transition signifies a natural evolution of his career, enabling him to apply his in-depth industry knowledge and analytical skills to help consumers make better purchasing decisions.