9 of the Best Marine Grease Options for 2023
Quicksilver High Performance Extreme Grease
Liquid Wrench Marine Grease
WD 40 Specialist Marine Grade Grease
Marine grease is one of those products you never think about until you need it. But when you do need it, you want to make sure you have the best stuff for the job at hand. You’ll find marine grease most useful for keeping your boat trailer wheel bearings in good working order, but it really does have a ton of other potential uses in and around the boat. You just need to make sure you have the right formula for the right job.
Choosing the Right Marine Grease
As with everything, there are plenty of choices on the market when it comes to marine grease. It’s an incredibly useful product that is chiefly used for trailer wheel bearings. That said, wheel bearings are far from the only application.
Quality marine grease is designed to be totally waterproof, thick enough to maintain hold in watery conditions, and able to maintain integrity even in high heat. Marine grease is thickened which allows it to act as a sealant as well and prevent it from letting more water in and wearing down over time. The combination of a lubricating compound with thickeners and other additives makes it a unique product. For those reasons you’ll find a number of potentially viable applications.
Boat Trailer Wheel Bearings
Your boat trailer is going to be going in and out of water, possibly even salt water, all the time. They can come in contact with not just water but various pollutants that may be in the water around the launch. Not to mention the muck and slime that can build up over time as well. This can take a toll on wheel bearings if they are not properly lubricated. On top of that, if you’re hauling the boat up and down the highway frequently, those tires are being put under a lot of stress. That means the wheel bearings need to be well maintained.
Marine grease keeps your wheel bearings moving slick and smooth. If you’ve ever tried to make use of a trailer that was not properly greased or has not been used in years, you may know how tough it can be. Unlubricated parts will seize up badly and make your job a lot harder.
Strictly speaking rollers don’t always need to be lubricated and not every boater will do so. But if you find yours moving a little sluggishly as you try to load and unload your boat, it could definitely be worth the effort to do so. One thing to be wary of here is the type of lubricant versus the type of roller. Cheap rubber rollers aren’t always good with different chemical compounds so the result could be dangerous. But higher quality rollers made of things like polyurethane and PVC should be able to handle whatever formulation you apply.
Winches and Reels
If you’ve ever tried to manage a winch that has been sitting out in a parking lot for a few years without being moved, you may know just how tough a job this can be. The elements can really make these seize up. Proper maintenance with marine grease will ensure a smooth-running winch as well as reels and other moving parts. You don’t need to slather a ton on, either. Just enough to keep things loose and easy to move.
No, you don’t need to keep your electronics greased up. That said, treating electronic contact points on a boat with a silicone lubricant is a good idea. Because of the environment things like wires, plugs, solder joints and more are going to succumb to the elements much faster on a boat than they would in your home. If you boat in salt water it can be even worse. And if you’re the kind of person who likes to do their own wiring, then this is a great final step in the process.
A quick application of silicone paste on the contact points and exposed metal in your electronics will ensure that moisture can’t get in. Over time, corrosion can slowly degrade the functionality of all of your electronics. You waste more electricity to get a poorer result because of it. So keeping things clean and resistant to moisture will ensure better battery efficiency and also a longer life for your electronics.
Rust and Corrosion Protection
In addition to general lubrication, you can enjoy the benefits of corrosion resistance with the proper marine grease. The thick formula clings to metal parts and offers protection against moisture, like a sort of greasy raincoat over the important moving parts of your boat and trailer. Obviously this will wear down over time as a result of heat and movement wearing the coating thin, but proper maintenance can ensure your boat and its part stay relatively rust free where it counts for a very long time.
Types of Marine Grease
People who are new to boating may not be aware of just how many options there are in the marine grease world. It’s not just different brands, it’s different compounds. Think of it like oil you use in your kitchen. You may have olive oil, but you can also use corn oil, avocado oil, peanut oil, grapeseed oil and probably a dozen more. Each has different strengths and weaknesses. Marine grease is similar.
One thing you want to be aware of is that mixing grease types is never a good idea. Like most chemical compounds, just because they’re similar in function doesn’t mean they play nicely together. If you mix the wrong kinds of marine grease together you could cause both to break down and work poorly, putting your trailer or boat at risk for damage. Remember to only use like products together. If you want to switch, you’ll want to do a thorough cleaning ahead of time.
Lithium is a metal and has countless practical uses in the world – they even make medications out of it. But in grease compounds it’s especially useful in marine applications. Lithium-based grease can handle temperatures up to 250 F. That means it’s a solid choice for general lubrication in and around the boat. You’d use this for non critical applications where overheating is not a risk factor. But what if you need higher temperatures? We’ve got that covered.
White Lithium Grease
This is a different product so don’t get them mixed up when you’re comparing. White lithium grease is a multipurpose grease and is ideal for metal on metal lubrication, so you can use this for your wheel bearings, for instance. It’s also a superior corrosion-resistant formula, which is another reason it’s helpful in bearings and other parts that get routine exposure to the water.
Lithium Complex Grease
Another lithium based compound, this version has more additives. They boost the temperature effectiveness, allowing this kind to handle much higher heat. Some lithium complex grease formulations can function up to temperatures of 350 F. That should be more than enough for most marine applications.
This is another general purpose grease but we don’t recommend this for something like wheel bearings. It’s obviously formulated for marine use but it’s more limited to things like hinges and runners. It’s not designed to handle high temperature applications and it’s also not particularly good with water. So if something is going to be immersed in the water, like your trailer wheels, this isn’t the best option.
Calcium Sulfonate Grease
With a little formula tweak, calcium sulfonate turns calcium grease into something much more effective. This formula is great for both wet and moist environments and also high temperature applications. This can operate up to 325 F and can also manage as low as -40 F as well, should you ever need to move your boat and trailer in the extreme cold.
Most marine greases are not silicone based but we did recommend a couple. It’s not necessarily the best choice for wheel bearings or your propeller, but it can be extremely useful on a boat. In particular, if you want to extend the life of your boat’s electronics, consider a silicone paste. Because of its rust and corrosion protection, if you use some of this on electrical connections for things like your bilge, radio, lights, security system and really anything you have wired on the boat, you can keep them running better and longer.
Aluminum Complex Grease
I didn’t recommend any of these and it’s for two reasons. One, there just aren’t a lot of good quality marine-specific aluminum complex greases out there. And two, they’re usually a lot more expensive anyway.
Do Boat Trailer Bearings Really Need Lubrication?
Wheel bearings are essentially a form of mechanical lubrication. Their job is to reduce friction to increase ease of movement. Rollers, ball bearings, all of them perform the same basic task. It’s a mechanical solution to a physical problem. The result is a smooth moving machine, in this case a wheel. But even though they’re designed to keep things moving smoothly, time and the elements can take their toll. Adding a marine lubricant to the mix ensures added protection, resistance to those elements, and lubrication to increase or maintain the smooth movement you need.
Trailer manufacturers typically detail in the owner’s manual how often wheel bearings need to be lubricated. It’s not a regular event – it’s probably best to do it once at least a year, depending on how much use your trailer gets. Even land-based trailers that never see open water typically need to be lubricated that frequently, so it’s all a part of standard upkeep and maintenance.
One thing to remember is that smaller wheels take on more abuse so the smaller they are the more frequently they’ll need lubricating.
How to Grease Your Bearings
When it’s time to use your boat trailer bearing grease, the process should not take too much time. You’ll need to get your trailer up on jacks and make sure it’s secure to get access to the wheel bearings. Once it’s up, remove the hub cover if you have one in place. If you have caps then you may need to bang them out of the way with a hammer or mallet to get them off and expose the bearings. This will give you access to the grease zerk in the center of your wheel. There should be a rubber cover or gasket of some kind on top that you’ll need to pry loose with a screwdriver as well.
Once the grease zerk is exposed you can line your grease gun up with it. Spin the wheel and begin forcing the grease inside. The idea here is to use the spinning motion to ensure even coating and, at the same time, force out the old grease evenly. As the old grease comes out, wipe it away and then continue spinning to get the rest of the grease in place. Make sure you clean the old grease thoroughly. If it gets on your brakes then you could end up having a serious accident.
Marine Grease vs General Purpose Lubricants
There are literally hundreds of different lubricants you can buy right now. Many of them advertise a wide range of uses from under the hood of your truck to ensuring your garage door opens smoothly. But you do want to make sure what you’re buying is marine grease in specific. The way marine grease has been formulated to handle moisture is critical. It offers far better water resistance than most general purpose lubricants and that’s going to be essential.
Using a non-marine grease could result in you having to reapply the grease far more often than you want to. That’s because it’s likely not a waterproof grease. That will waste your time and money. It could also be bad for the environment depending on what type of grease you’re using. So do yourself, your wallet and the environment a favor and make sure it’s the right stuff for the job.
Other Things to Consider
Who would have thought there was so much to know about grease, right? Well, there are still a few other factors you’ll want to keep in mind as well.
This is something you may not realize the intricacies of until you actually try to use the product. You’ll either need some kind of grease gun or the product should have a nozzle or other applicator tool included with it to allow you to actually get the grease where you need it. Be aware, though, that some are just in tubs. That means you’re going to need to figure out on your own how to apply it where it needs to go. So factor in the cost of buying a grease gun or other applicator into the total if you don’t have one already.
We covered some of the temperature ratings for common types of marine grease earlier. Those are good to keep in mind. Wheel bearings are subject to friction so that means the temperature can get rather hot. You want a grease designed to withstand that temperature. If you choose a lower temperature grease, the friction will create too much heat which will cause the grease to thin out and drip off, basically melting it away. By the time you take a single trip you could have lost all of the benefits of the grease and be putting your trailer and boat at risk as a result.
Every kind of grease has a viscosity rating but they don’t always list it for products like these. You’re probably more familiar with motor oil viscosity, for instance. In terms of marine applications, you may not need the exact number but you can get an idea from looking at it if it’s going to be as thick as you need it to be. You want a viscous grease that is going to stick and stay put. That’s why this stuff is called grease and not oil. It’s been thickened specifically to give it that jelly-like texture so it can hold fast even on moving parts in the water. If your grease is too thin the heat, water and movement will wear it down too quickly.
This is another big reason to use a product labeled specifically for marine use rather than a general use compound. Marine specific products should be designed with environmental safety in mind. That means they are non-toxic and won’t harm waterways and wildlife. This is a big deal and should be something that every kind of marine grease can get on board with. As boaters we need to be stewards of the environment and lead by example when it comes to taking care of it. If every boater were to use dangerous and polluting grease, then all of us would have to endure oily, polluted waters and none of us would be having a good time boating. Always make sure it’s designed for marine use and is safe for the environment.
It’s likely that you’re going to have leftover grease that you store in the boat, the garage, or wherever. Make sure you’re storing it according to the directions from the manufacturer. A cool, dry place out of the light is best. Just because it’s designed to work in high temperatures and even underwater doesn’t mean it will store well in conditions like that. Improper storage can potentially cause it to separate or degrade over time.
You will see some greases advertised as having a certain NGLI number. For marine wheel bearing grease it’s usually NGLI 2. That stands for National Lubricating Grease Institute. Yeah, that’s a thing. It’s a measure of the relative hardness of grease used for lubrication.
NGLI 2 grease is “normal” hardness. Which is to say it should have a consistency like peanut butter. For comparison a 3 should be like vegetable shortening and 4 should be like frozen yogurt. Normal cooking oil as a 000 rating. Tomato paste is a 1.
The Bottom Line
As you can see, marine grease covers a heck of a lot of ground. So many types and applications can make it seem a little overwhelming at first. But knowing what you need it for really helps narrow the field. Regardless of the application you’re looking for, just make sure you get something truly marine grade. That way your boat or trailer will be able to keep working for the long haul, and the environment won’t take a beating, either. As always, stay safe and have fun.