Best Grease For Boat Trailer Wheel Bearings

Choosing the right grease for your boat trailer's wheel bearings is essential to ensure a smooth ride. While it may seem like a mundane task, proper maintenance can save you from being stranded on the side of the road with a burnt-up or seized wheel bearing. The key factor to consider when selecting a grease is its compatibility with marine environments, as standard greases may not be able to resist the water that your trailer wheels encounter during boat launch.

Marine-grade greases are designed specifically for this purpose and typically have additives that make them hydrophobic, helping to repel water and protect against corrosion. Some recommended options include Sta-Lube Marine Grease, Mission Automotive Waterproof Marine Grease, Lucas Oil Marine Grease, and CRC Marine Boat Trailer and 4x4 Wheel Bearing Grease. These greases are known for their water-resistant properties and ability to withstand harsh marine conditions, making them ideal for boat trailers.

In addition to selecting the right grease, it is crucial to maintain and service your trailer's wheel bearings regularly. This includes re-greasing the bearings at least once a year, preferably at the end of the season, to prevent rusting during the off-season. By choosing a high-quality marine grease and maintaining your trailer's wheel bearings, you can ensure a safe and enjoyable boating experience.

Marine grease vs general-purpose grease

Marine grease and general-purpose grease are both lubricants used for machinery and equipment maintenance. While they share some similarities, there are also significant differences between the two in terms of composition, performance, and suitability for specific applications. Understanding these differences is crucial for selecting the most appropriate grease for your boat trailer to ensure optimal performance and protection.

Composition

Both marine grease and general-purpose grease are composed of three basic components: a base oil, a thickener, and additives. The thickener is particularly important as it determines how the grease behaves under different conditions. Marine greases typically use water-resistant thickeners such as anhydrous calcium, aluminum complex, or lithium complex. Calcium sulfonate greases are also an excellent choice for marine applications due to their superior corrosion resistance. On the other hand, general-purpose greases may use thickeners like sodium grease, which has poor water resistance.

Performance and Suitability

General-purpose grease is readily available and affordable, making it suitable for a wide range of applications. However, it may not be the best choice for marine or boat trailer applications as it can wash away quickly when exposed to water, leaving components vulnerable to corrosion and contaminants. Marine grease, on the other hand, is specifically formulated to perform well in high-moisture environments. It stays in place, providing enhanced protection against water and corrosion. This durability also makes marine grease an excellent choice for applications beyond marine use. However, due to its special formulation, marine grease may be more expensive and less readily available than general-purpose grease.

Best Practice

When it comes to greasing boat trailer bearings, it is generally recommended to use a high-quality synthetic marine grease that is water-resistant. While automotive bearing grease can be used in a pinch, marine wheel-bearing grease is superior, and synthetic marine-wheel bearing grease is the best option. It is important to clean out old grease before repacking and to avoid mixing different types of grease if possible.

Best marine grease brands

When it comes to choosing the best marine grease for your boat trailer, there are several factors to consider, including the type of grease, its compatibility with other greases, and its water resistance properties. Here are some of the top marine grease brands that are suitable for boat trailers:

Sta-Lube Marine Grease

Sta-Lube offers a range of marine greases suitable for boat trailers. Their products, such as the Sta-Lube SL3120 Water-Resistant Marine Grease, are designed to resist water even under severe conditions. It is a blue, tacky, aluminium complex grease that provides adhesive and non-blend characteristics. Sta-Lube's marine grease has received positive reviews for its quality and functionality, with users noting its water resistance and performance in wet applications.

Quicksilver Marine Grease

Quicksilver offers two high-performance marine grease products: Quicksilver 2-4-C Marine Grease and Quicksilver High-Performance Extreme Grease. The 2-4-C Marine Grease is a versatile lithium-based grease that offers excellent resistance to oxidation and degradation. It is suitable for a wide range of applications and temperatures and can be used on outboard motors, sterndrives, and trailer wheel bearings. The High-Performance Extreme Grease, on the other hand, is more heat-tolerant and is ideal for sterndrive drive shaft splines, gimbal bearings, and trailer wheel bearings.

LubriMatic Marine Grease

LubriMatic Marine Trailer Wheel Bearing Grease is specifically designed for boat trailer wheel bearings. It is a high-quality synthetic marine grease that provides water resistance and advanced protection for your bearings. LubriMatic also offers a range of grease guns and bearing packers to assist with the application process.

Special Auto/Marine Grease by Lubriplate

This grease is recommended by boaters for its performance and affordability. It has a drop point of 400°F, making it suitable for high-temperature applications. Lubriplate's Special Auto/Marine Grease is a good choice for those looking for a balance between performance and cost.

Other Options

Other marine grease options include the Pennzoil Marine Wheel Bearing Grease, OMC Triple Guard, and AtomLube Ultra Heavy Duty Red Grease. When choosing a marine grease, it is important to consider the specific requirements of your boat trailer and the conditions it will be exposed to. Always refer to the manufacturer's recommendations and ensure compatibility with any previously used grease.

Grease viscosity and letter ratings

When selecting a grease for boat trailer wheel bearings, it is important to consider the grease's viscosity and letter ratings, which indicate its consistency and intended application.

Grease Viscosity

The viscosity of a grease refers to its thickness or resistance to flow. It is typically measured on a scale of 0 to 6, with 0 being the softest and most fluid-like, and 6 being the hardest and most solid-like. The National Lubrication and Grease Institute (NLGI) has established nine consistency grades (000, 00, 0, 1, 2, 3, 4, 5, 6) for grease, with NLGI #2 being the most commonly used grade for automotive and heavy-duty applications. Softer grades are often used for improved pumpability or low-temperature service, while harder grades are used to prevent leakage and are better suited for sealing concerns.

Grease Letter Ratings

In addition to viscosity, greases also carry letter ratings that indicate their intended application and performance level. The letter "G" indicates that the grease is certified for use in automotive wheel-bearing applications, while "L" denotes use on an automotive chassis for lubricating components like tie rods, universal joints, spindles, or steering knuckles. These letters are typically followed by "A", "B", or "C", indicating the quality of the grease: "A" for Good, "B" for Better, and "C" for Best. For example, a grease labelled "GC" is considered the best for automotive wheel-bearing use. Greases can also carry both "G" and "L" ratings, indicating their suitability for both chassis and bearing use. If a grease is labelled "GC-LC", it has received the highest possible rating for automotive chassis and bearing applications and meets OEM requirements.

Grease compatibility

When it comes to grease compatibility, it is important to remember that not all greases are created equal. Even greases labelled "marine" may be incompatible with boat trailers. Therefore, it is recommended to only change the type of grease when cleaning and repacking bearings.

Not all grease thickeners are compatible with each other, so it is essential to select a grease with the same or compatible thickener when replenishing old grease. If the type of grease being replaced is unknown, it is best to clean out as much of the old grease as possible before adding new grease.

For boat trailers, it is generally recommended to use a high-quality synthetic marine grease that is water-resistant. While automotive bearing grease can work in a pinch, marine wheel-bearing grease is better, and synthetic marine-wheel bearing grease is the best option.

When it comes to specific products, some options mentioned in forums include Mystik #2 high-temp grease, Sta-Lube Marine Boat Trailer grease, Lucas Marine grease, WD40 Marine Grease, and Amsoil Synthetic Water-resistant grease. Additionally, it is worth noting that some people choose to use general-purpose grease, such as white lithium grease, in a pinch for their boat trailer bearings.

Grease colour

When it comes to the colour of grease, it is important to note that different colours may indicate different types of grease with varying properties and applications. Here is an overview of the common colours of grease and their characteristics, specifically regarding their suitability for boat trailer wheel bearings:

• Red Grease: Red grease is typically lithium-based and is often marketed as "waterproof" or "water-resistant". However, it is generally not recommended for use in wheel bearings, especially in marine applications. Red grease is more suitable for lubricating parts that slide together under pressure, such as brake calipers. It can be used in a pinch for boat trailer bearings, but it is not the ideal choice.
• Green Grease: Green grease is also usually lithium-based and may offer extra heavy-duty performance compared to red grease. However, it is not specifically designed for wheel bearings and may have poor water resistance. Green grease can be an option for boat trailer bearings, but it is not the best choice if your trailer is frequently dunked in water.
• Blue Grease: Blue grease, also known as marine grease, is specifically designed for marine applications and is highly recommended for boat trailer wheel bearings. It is typically an aluminium complex grease or a calcium-based grease, providing superior water resistance. Blue grease is designed to resist water even under severe conditions and is suitable for both fresh and saltwater use. It is also non-flammable, making it a safe choice for marine environments.
• White Grease: White grease, also known as white lithium grease, is a multi-purpose grease that is typically lithium-based. It is easily identifiable by its white colour and is commonly used for lubricating lube points on vehicle chassis, farm equipment, and industrial machinery. White grease is not specifically designed for wheel bearings and is usually not water-resistant, making it less suitable for boat trailer applications.

When choosing a grease for boat trailer wheel bearings, selecting a marine-grade grease is crucial. Blue grease, or marine grease, is specifically designed for this purpose and offers excellent water resistance, making it the best choice to protect your trailer bearings from corrosion and water damage. While other colours of grease may work in a pinch, they may not provide the same level of protection and performance as marine grease. Therefore, to ensure the longevity and smooth operation of your boat trailer, opting for a high-quality blue marine grease is highly recommended.

Frequently asked questions