Common Problems With Dewalt Grease Gun (Solutions Included)

The Dewalt grease gun is a 20v battery powered grease gun that powers through clogged grease fittings, what that means is that you can apply grease to most machine like tractors, cars and industrial machines using the Dewalt 20v grease gun in very tight spaces like in-between the wheel and the axel of a car using the 42 inch hose that the grease gun comes with. But with a tool that offers such convenience there’s bound to be some underlying problems involved. Suffice to say that the Dewalt grease gun is one of the most powerful grease guns ever made.

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How Does It Work?

Grease is a lubricant (a substance used to reduce friction between objects or surfaces) that clings to a machine’s moving surface without the painstaking reality of an oil leak (as you would with an oil-based lubricant.) The Dewalt grease gun is used to effectively apply this grease onto machine parts when the trigger on the gun is pressed. The grease gun then releases a sizable amount of grease through its flexible 42 inch hose. The grease gun is powered by a 4Ah battery that has an incredible amount of runtime. Nevertheless grease guns are designed to remove the hassle and messiness that comes with applying grease traditionally (that’s to say with your hands.)

1. The Grease Gun Is Leaky

Most grease gun manufacturers will claim that their grease gun solves the problem of grease leaking out of the grease gun, one of them being Dewalt but this is seemingly impossible. However when your Dewalt grease gun starts leaking grease that is not necessarily to say that the grease gun is broken rather a couple of other problems may be causing the messy issue. Even though grease is what’s known as a thick liquid, it is susceptible to leakage under very high conditions which the Dewalt grease gun can produce.


  • All manner of grease gun will leak grease at some point no matter what is done, but considering the following will help manage the problem.
  • It is important to take note of the place where you store the Dewalt grease gun. The hotter or warmer the place you store the grease gun, the more likely it will melt and start to leak. Store the Dewalt grease gun in a cool and dry place.
  • The type of grease (in relation to brand) also plays a huge role. Some grease manufacturers have invested heavily in negating the leaking grease gun problem. It would be wise (although more expensive) to choose a more established brand as opposed to other brands.

2. Grease Gun Isn’t Pumping

For the Dewalt grease gun to pump out grease through its 42 inch hose, it needs to be letting in air. Air pressure plays a huge role in the grease gun’s function. This problem occurs when no air is coming into the machine and so when pressing the trigger, nothing happens. Grease can also be the cause of this problem, if it makes its way out of the barrel and onto other parts of the gun. Clogging the valves and holes that let in the air.


  • To help with this problem it is advisable to loosen the barrel for a bit to make sure that enough or more air is coming into the grease gun, then pressing the trigger once again.
  • Sometimes it is just a matter of pressing on the trigger for as long as until the grease gun responds and starts pumping. As mentioned before grease is a thick liquid so it takes a little longer to make its way through the grease gun.
  • It helps to clean the grease gun with a clean towel once all grease has been cleared out of the tool.

3. Rod Won’t Pull Back

The Dewalt grease gun has a rod as part of the metal barrel where you put the grease. The rod is used to push grease into the gun where it can be expelled through the hose. At the tip of the rod (inside the barrel) is a plunger; which is a flat surface that covers the entire circumference of the barrel so that a lot of grease is pushed out.

  • But for this to work the rod and plunger need to keep a uniform amount of pressure at the back as it is moving upwards, which causes this problem. It happens because the pressure becomes uneven such that there’s too much pressure at the back and the rod won’t pull back.


  • To release the pressure or air build up you should unscrew the purge valve, unscrewing the purge valve will immediately release the air and this make the rod on the Dewalt grease gun movable.

4. Grease Gun Motor Isn’t Running

When you pull the trigger on the Dewalt grease gun and the motor is not running it probably has more to do with the battery than anything else. The motor is responsible for creating or generating the pressure necessary for pushing the grease out of the grease gun. So when the motor doesn’t run, the grease gun doesn’t work.


  • When using the grease gun, or before you start, using the grease gun it is important to make sure that the battery is fully charged. The Dewalt grease gun battery can last for quite some time.
  • When the motor isn’t running it means no power is making its way to the motor. If it so happens that the battery is fully charged then it is a fault in the internal wiring of the grease gun. In which case you would need to take it to an accredited Dewalt repair technician.


Ultimately the Dewalt grease gun is a good tool to have. Because it can do what it is supposed to. Although it has its share of problems, it seems they’re only but mandane and miniscule. It is essential for lubricating other machines like cars and trucks, and many many more in places you wouldn’t be able to normally reach with your bare hands or fingers. And when your daily life consists mostly of those machines then having the Dewalt grease gun is a must.