As machines tackle challenging tasks like digging and breaking through hard materials, their moving parts endure a steady stream of friction.

If a machine isn’t properly lubricated, this friction can cause metal components to grind against each other, leading to excessive wear. Keeping your machine well-lubricated through proper greasing is a critical part of heavy equipment maintenance.

From attachments and buckets to pins and bushings, nearly all of a machine’s moving parts require adequate, frequent greasing to stay in working condition.

Not all grease is made equally, however. In fact, there is a wide array of grease and lubricants available on the market, and knowing which one to choose is no easy task. In this guide, we’ll introduce the most common types of grease used in modern heavy equipment. We’ll delve into the attributes of each type, helping you choose the best grease for your machine.

Types of Heavy Equipment Grease

Grease used in heavy equipment is most commonly made from either mineral or synthetic oil. Various types of grease are differentiated by their viscosity level and any special additives they contain.

NLGI Rating

The National Lubricating Grease Institute (NLGI) maintains standards for grease viscosity. Grease with a lower NLGI rating is less viscous, whereas grease with a higher NLGI rating is more viscous.

For example, an NLGI #1 grease will have a more liquid consistency at room temperature, while an NLGI #6 grease is semi-solid at room temperature.

Choosing a grease with an appropriate NLGI rating is important because components that generate a lot of heat will generally require more viscous grease, while other components may require less viscous grease.

It’s also common for machines to require a more viscous grease (higher NLGI) during hot summer months, while requiring a less viscous grease during the cooler months. This is especially true in hot climates, where high temperatures cause grease to thin out and become less viscous.

Grease Additives

In addition to viscosity, additives are another important consideration when comparing types of grease. Some types of grease contain additives that alter or enhance the properties of the grease.

For example, one common type of grease contains molybdenum disulfide (moly). Grease containing moly has a superior capability for getting into the tiniest spaces between components. It’s used frequently for high pressure and/or high-impact use cases.

Marine grease, which contains a lithium complex, is another popular type of grease. The lithium complex additive makes the grease thicker and more water-resistant, making it ideal for use in wet conditions.

Common Types of Grease

Here are some popular types of grease and their applications:

1. Moly Grease. Molybdenum disulfide, commonly known as "moly," is a solid lubricant that imparts excellent anti-friction properties to the grease. Moly grease is particularly suited for heavy equipment machinery subjected to extreme pressure and heavy loads
2. Multi-purpose Grease. This grease is a versatile option designed to cover a broad range of applications. It’s formulated to provide general lubrication and protection across a wide spectrum of components. Multi-purpose grease offers moderate performance in terms of load capacity and protection against wear.
3. Synthetic Grease. Synthetic grease is engineered using advanced synthetic base oils and additives, resulting in enhanced performance characteristics compared to conventional mineral-based greases. This type of grease is formulated to withstand extreme temperature variations, heavy loads and corrosive environments.
4. Hammer Paste. Hammer paste is a specialized grease designed to address the unique demands of hydraulic hammers and breakers. This grease is specifically engineered to withstand the heavy shock loads, high pressures and repetitive impacts encountered in these applications.
5. Marine Grease. Marine grease is tailored to heavy equipment operating in maritime or water-immersed environments. Its standout feature is its water-resistant properties, which prevent water intrusion and subsequent corrosion on equipment components.

Choosing the Right Grease for Your Needs

To find out which type of grease to use with your machine, begin by reading its service manual. Your machine’s service manual will provide the type of grease to use, as well as the location of your machine’s grease points.

Keep in mind that different components on your machine may require different types of grease. Your machine’s service manual will indicate the components that require greasing with the suggested type of grease to be used.

It’s important to remember that different types of grease cannot be mixed. So, if you decide to switch the type of grease you are using, you have to totally flush out the current grease before replacing it.

Best Practices for Greasing Heavy Equipment

While many operators wait until they hear grinding to grease their machine, this approach inevitably leads to excessive breakdowns and costly repairs. Instead, you should plan to grease your machine according to a well-defined schedule.

Greasing your machine frequently and regularly is the best way to prevent excessive wear on your machine’s friction components and save on repair costs.

Here are some greasing best practices to keep in mind:

1. Grease often. For many components, greasing should occur daily. Your machine’s service manual should provide greasing intervals for each component on your machine.
2. Use the right type of grease. For best results, use the type of grease indicated in your machine’s service manual. It’s important to note that certain components may require a different type of grease than the rest of the machine.
3. Keep your zerks clean. If dirt builds up on the outside of your machine’s grease fittings, you may inadvertently force dirt into the machine when you grease it. To avoid this, keep your machine’s zerks clean, especially before adding new grease.
4. Take the weather into account. During hotter months, you may need to use a grease with a higher viscosity. Similarly, during the winter you may need to use a grease with a lower viscosity.
5. Don’t over grease. Over-greasing your machine’s components can cause grease to leak out onto the zerk, which could attract dirt and dust. While it’s important to grease each component adequately, there’s no need to over-grease.
6. Inspect for worn components. While greasing your machine, take the opportunity to check for worn hoses and grease fittings.

Final Thoughts

Keeping your machine well-lubricated by greasing it frequently is one of the best ways to prevent excessive wear and costly breakdowns.

The MechLink Shop carries OEM and aftermarket parts for all aspects of your construction fleet. If your machine has been impacted by bad greasing habits, MechLink can help supply the components you need to get it back into prime condition. Can’t find the specific part you’re looking for? Reach out to our parts experts and get personalized assistance.

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