Milwaukee M12 Vs. M18 Grease Gun: What's The Difference & Which Do Users Prefer?

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Grease guns are an essential tool you'll want to have for working on your project car. In addition, these devices are also used for industrial, agricultural, and construction purposes, so it's definitely a regular tool in many professionals' kit. There are a ton of grease gun options out there, including manual, hand-pump, and air-powered ones. Manufacturers like Milwaukee, however, have developed battery-powered options that are perfect for people who need to grease things often.

The red-and-black power tool manufacturer offers two highly rated grease gun options that you can choose from: the M12 Cordless Lithium-ion Grease Gun and the M18 Cordless 2-Speed Grease Gun. As their names suggest, both Milwaukee options are cordless, made of aluminum, and covered by the power tool manufacturer's 5-year limited warranty if purchased from an official retailer. In addition, they both use the same air bleeder valve technology and batteries that are compatible with dozens of other Milwaukee power tool devices. While you can use both Milwaukee battery-powered grease guns in similar ways, there are some key differences in both their form and function. Let's compare each product to help determine which one may be better for you and your everyday greasing needs.

Between the two Milwaukee grease guns, the most obvious point of comparison is that they run on different battery systems. As we've mentioned before, Milwaukee's M12 and M18 batteries have different capacities, price points, and weights. However, M18 tools are perceived to be the better option for professionals or those who need more longevity and power. Not to mention, they're known to have more tools that are compatible, since they can handle the needs of bigger tools.

In terms of size, the M18 and M12 grease guns have the same length (14 inches) and width (3 inches). However, the M18 is more than double the height of the M12 at 20.75 inches, a little over 2 pounds heavier, and has an extra foot of hose length at 48 inches. As for functionality, the M18 has two speed settings while the M12 only offers one. Additionally, the M18 can work with up to 10 cartridges with each full battery, whereas the M12 only has the capacity for seven. Although the M18 has some advantages over the M12, you'll have to decide whether the increased power and longevity is what you need. It comes at a cost, with the M18 model  priced at $186 on Amazon. That's about $60 higher than the M12 model.

Users tend to be satisfied with both Milwaukee grease guns. On the official Milwaukee website, the M18 option has generated an average rating of 4.6 stars from more than 400 customers. Not to mention, an impressive 93% of customers thought that it was worth the recommendation. In fact, there are several positive remarks from users that have used it in both personal and professional settings. 

The tool performs similarly well in Amazon reviews, with 83% of buyers giving it a perfect 5-star rating. Many users report that they love its build quality and how it's easy to clean compared to other types of grease guns. One reviewer said they had some difficulties priming the M18 model, while others shared that it tends to waste grease cans.

As for the M12 grease gun, more than 130 people have given it 4.5 stars on the official Milwaukee website. Over on Amazon, it has a slightly lower percentage of users who gave it a perfect rating at 76%. Most users are still very satisfied with it, although some reviewers noted that it could perform better when it comes to power and battery life.

This article is not intended as an endorsement of either product. Instead, it's meant to compare user reviews on both Milwaukee options to help determine how these products work with real-time use. In addition to considering these items' physical specs like overall size, battery usage, and hose length, we also took a close look at user ratings across multiple websites. We included each product's average rating with major online retailers, such as Amazon and the official Milwaukee site. In addition, we included what things people liked and didn't like about them to help you decide if its advantages outweigh its criticisms from both ordinary homeowners and professionals.