Will a 3 Gallon Air Compressor Run an Impact Wrench?

You’re going to buy an impact wrench, but like most regular people, the air pressure you have isn’t more than 3 Gallon. ‘Will a 3 gallon air compressor run an impact wrench?’ you start to think. Well, we’re going to give you the answer, and also, if it’s a yes or even a no, we’ll let you know why we’ve come to that conclusion.

Also, we’ll tell you which one is ideal for you. So, why waiting? Read this write-up to know better.

Can You Run an Impact Wrench with a 3 Gallon Air Compressor?

One of the things some people forget to take into account is the size of the air compressor. It is common knowledge that air pressure is one of the key factors when it comes to running an impact wrench.

But the size is important too. Since impact wrenches aren’t tools you would use continuously, you can use a good quality portable air compressor to run them. Here is the thing, though – you still need an adequately powerful air compressor.

Most people will actually have 3-gallon air compressors in their homes or their workshops. They are quite inexpensive, readily available, and are great for beginners.

So, that naturally begs the question will a 3 gallon air compressor run an impact wrench? Unfortunately, it won’t. As we mentioned before, the size and the air pressure are the key factors.

Air compressors with 3-gallon measurements are quite weak and certainly don’t produce the amount of CFM needed to run a high-quality impact wrench. Even if you talk about the smallest impact wrench, it will need at least 1 to 1.5 CFM of air pressure to run properly.

Most 3-gallon air compressors produce only about 0.5 CFM of air pressure. Now, you can immediately see the problem, can’t you?

That’s not the only problem. You have the small size of the air compressor to account for as well. Let’s just say you manage to run an impact wrench with a 3-gallon air compressor, hypothetically.

Due to the smaller size, you would need to refill it constantly. When you’re working away, constantly stopping your workflow to refill the compressor will not only be distracting and annoying but will increase the time you need to finish the job.

Taking all things into consideration, it really isn’t worth it trying to run an impact wrench on a 3-gallon air compressor.

What Size of Air Compressor Is Good for Impact Wrench?

Since 3 gallon air compressors are a no-go. What size do you need then? Before we tell you the minimum requirement, let’s dive into what you need to be looking for actually.

The larger the air compressor’s size, the less time you need to spend refilling it. Also, depending on the size of the impact wrench you have, the more CFM you would ideally want.

If we were to give you a minimum spec, a 6-gallon air compressor with at least 4 CFM is good. That’s basically double the gallons compared to a 3 gallon one. The larger size helps you work for a longer duration of time, and of course, the high CFM rating means you can use the wrench reliably.

This is basically the minimum requirement, though. We would recommend you go for something a little bigger, like a 10 gallon one. You also need to take the cost into account as well.

Larger sizes will naturally mean more costs. But since you can work for longer and as impact wrenches are used intermittently, it should balance it out. Although, the sweet spot for you might be different.

You need to check what size works for you the best. But as a general rule of thumb, going any lower than 6 gallons and 4 CFM is not recommended.

However, if you have a smaller impact wrench, you can get a smaller air compressor. For example ¼” impact wrenches can be easily operated with 1 or 1.5 CFM air compressors. It won’t hurt if you have a little more oomph, but this range is fine for small wrenches.

Wrapping Up!

So, will a 3 gallon air compressor run an impact wrench? The straight answer is NO! 3-gallon compressors aren’t powerful enough even for the smallest impact wrenches.

A 6-gallon wrench with at least 4 CFM is the least you can have. As for the price, you can get a good-quality air impact wrench under 100 dollars near you as well.  All you need to do is look at the right place.



Shawkat is a passionate home and auto mechanic who enjoys sharing his knowledge with others. He has been working on cars and homes for over 9 years and has a wealth of experience to share. From indoor tools to outdoors, crafting to automotive, you will see his passion for tools. And he is not alone here, either. He collaborates with other users to give you the best possible tool experience. As the founder of Geartoolsbuddy, Shakat is always happy to help people with their queries and doubts about power and hand tools.