You can use an impact wrench and a torque wrench to accomplish a lot of the same things. For example, both are useful for tightening bolts, nuts, and so on. Naturally, this leads to the question of which one you should be used in which circumstances. That is what I have written this article to help with. I will explain to you the relative merits of each tool and examine when you should be using each one.
Is an impact wrench the same as a torque wrench?
No. The main difference is that an impact wrench is a power tool that can exert a high impact force to tighten and loosen stubborn fasteners. On the other hand, a torque wrench is a hand tool with torque control which enables you to accurately tighten the nuts and bolts.
Torque Wrench Vs Impact Wrench Comparison Chart
In this section, I quickly want to go over the differences between the two kinds of tools.
| Torque Wrench | Impact Wrench | |
| Key Feature | Precise torque control | Very powerful but less control |
| Power Source | Manual wrench | Air, Battery or Electricity |
| Ease of Use | Long hours of operation can result in excessive fatigue to the worker. | No excessive strain on wrists. Easy to work all day long. |
| Noise | No noise pollution | Loud tool. Use of ear protection is highly recommended. |
| Cost | Inexpensive | Air impact wrenches are affordable. Cordless version costs slightly more. |
Differences Between Impact Wrenches and Torque Wrenches
Although they both do many of the same jobs, they are obviously quite different tools otherwise. So, to make sure that everyone knows about the differences, let’s look at what are, in my opinion, some of the most important ones.
Manual Use Vs Powered
Probably the first, and easiest to spot, is the fact that one is a manual tool and the othered is a powered one. A torque wrench is very similar to a regular wrench meaning that the user supplies the power by manually turning it. An impact wrench is a power tool, it uses either air pressure or electricity to generate its power; the user just has to pull the trigger.
Speed and Durability
Another major difference between the two relates to durability. Impact wrenches can do huge amounts of work in a short amount of time and it won’t impact the tool at all. You could screw in hundreds of bolts and the tool will be the same as when you started. The same can’t be said for a torque wrench.
Torque wrenches aren’t meant to be used on jobs where you have to tighten dozens of bolts in a short amount of time because you could end up damaging the tool. They are more designed with precision work involving a few bolts at most.
Adjustable Vs Static Torque Output
But, by far the biggest difference is the fact that one is adjustable when it comes to its torque output while the other is not. Torque wrenches often come with some mechanism that lets you change how much torque the wrench puts out. Different torque wrenches use different methods for changing the torque output; some use electricity, some use an adjustable clutch, etc.
Impact wrenches are different animals altogether. With an impact wrench, you have a stated power output. If it’s an electric impact wrench, it will be based on the power of the battery. If it’s a pneumatic impact wrench, it will be based on the air compressor. In other words, you can’t really adjust the torque on an impact wrench. If you want significantly less torque or even more torque, then you have to essentially get a different size impact wrench.
However, if you do not need precise control of torque, you can reduce or increase the airflow in a pneumatic impact wrench to adjust speed. This will give you a very rough control over the output torque.
Just based on these differences alone, you can probably see why both of these tools have a role to play. To make it even clearer, I’m going to go over when I think you should be using one tool or another.
When to Go for An Impact Wrench
As you probably guessed from what I said in the differences section, the best jobs to use an impact wrench for are ones that require speed and force instead of precision. This plays to the strength of the impact wrench, which is the ability to quickly get a bolt or nut screwed in or taken out very quickly and with minimal effort on your part.
For example, if you are working on a large construction project like a house or another kind of building, then an impact wrench is going to make it a lot easier to deal with the potentials hundreds of bolts that need to be screwed in.
Likewise, a classic job where the impact wrench shines is when taking off or putting on a tire. Tires secured with lug nuts that need to be dealt with impacts for quick and easy removal and using a torque wrench would take a lot longer. An impact wrench can have a tire off or on in minutes if you know what you are doing.
When not to use an impact wrench?
Do not use an impact wrench to tighten the lug nut. You can remove a lug nut with an impact wrench and use it to quickly put the nut back. But you should always use the torque wrench to tighten it to the correct torque. Here is the right method to change the car tire with an impact tool.
When to Go for A Torque Wrench
Generally, you will be using a torque wrench in situations that are the exact opposite of situations where you would want to use an impact wrench. In other words, you want to use a torque wrench when you only have a few bolts or nuts to work with and when they need to have a specific amount of torque applied.
The most common areas where a torque wrench is used is when working with vehicles and bikes. When working on the internal part of a vehicle (like the suspension) you want to use a torque wrench because you must apply just the right amount of torque. You don’t want to risk applying too much and stripping a bolt. The same logic goes for working on bikes. The bolts there require a very specific amount of torque and you don’t want to risk applying too much.
Torque wrenches are also used in the assembly of machines, automobiles, mechanical assemblies and construction where the fasteners must be tightened to the exact torque to ensure proper clamping.
How about ratchet wrenches?
A ratchet wrench is a power tool similar to impact gun. However, they are used for different purposes. Here is a comparison between an impact wrench and ratchet wrench.
Conclusion: I hope that you found this article illustrating the differences between the two types of tools to be helpful. Hopefully, I cleared up any questions that you may have had regarding when to use either kind of tool.
Dan Miller is a professional toolmaker with extensive experience in the metalworking and tooling industry.
An avid DIY enthusiast and passionate hobbyist woodworker, Dan shares his expert knowledge here.