An impact wrench is a high-torque power tool used to tighten or loosen tough nuts and bolts. It is also known as impact gun, air wrench, air gun, torque gun, among other names. This professional instrument is mostly used by mechanics and workers of the metal fabrication industry because of its strength, high speed, and convenience.
The impact wrench has a square drive to which you attach a socket to grab around the nut or bolt. Then the motor applies continuous short blows (impact) of rotational force (torque) to it to either loosen it or fasten it. Traditionally, the strongest models are pneumatically powered, but nowadays electrical and hydraulic power sources are becoming a popular alternative.

What is an impact wrench used for?
An impact wrench is most commonly found in a mechanic’s garage because it makes removing lug nuts from cars and other vehicles quick and easy, with almost no effort on the part of the user. Any other industries that require high torque output for tasks such as heavy equipment maintenance or assembly lines would have an impact wrench in their toolbox. Since it is basically used for bolting and unbolting screws, the homeowner or enthusiast DIYer could use it for certain house repairs, changing a tire, or doing some car maintenance.
What is the difference between an impact wrench and an impact driver?
The impact wrench and the impact driver are similar only in name and looks because they are used for very different tasks. While the impact wrench is used for removing nuts or bolts, impact drivers are used for drilling long screws into wood or metal. Impact wrenches are more professional tools, heavier, and more powerful, whereas impact drivers are easy to operate and more useful for house renovations and DIY projects.
When not to use an impact wrench?
Even though impact wrenches are not as dangerous as other power tools can be, you still have to be careful not to damage the equipment you’re working on. You should not use an impact wrench if you:
- Do not have protective gear. Impact wrenches are extremely loud, so hearing protection is essential. Gloves, a face mask, and safety goggles are also important.
- Are wearing loose-fitting clothes or jewelry that could get in the way and cause an accident.
- Do not have the sockets designed specifically for your tool because they might slip, splinter, or break from the impact, leading to possible injuries.
- Be careful when tightening bolts or nuts because you can over-tighten them and damage both the equipment you are working on and the tool itself.
How much money does an impact wrench cost?
The cheapest pneumatic impact wrench starts at $30 on Amazon. One with more features such as adjustable speed, safety trigger, and non-slip handle can be purchased for $50, and the strongest heavy-duty wrench can go for as much as $3,000. Other hardware stores offer wrenches with 300 ft./lbs. of torque for $50, and they can go as high as $600 for heavy-duty pneumatic impact wrenches of 2,140 ft./lbs. of torque.
Cordless models with 200 ft./lbs. of torque start at $30, but they usually come without batteries. The most expensive options cost about $800, and they often include two batteries, a charger, and other accessories such as a case, and a set of impact sockets.
Where can I buy an impact wrench?
It will depend on whether you will use your impact wrench professionally or for DIY projects. Hardware stores will have a wide range of wrenches, particularly pneumatic and heavy-duty ones. However, your local Walmart will only offer you three pneumatic options that range from $30 to $150, and three cordless models that cost about $60, which are perfect for home renovations or DIY tasks.
Which impact wrench should I buy?
The impact wrench you add to your toolbox will depend on what you will use it for. The pneumatic impact wrench is the one that can provide the most torque, so it is the one you will definitely find in every mechanic’s shop. It is light and easy to use and being air-powered ensures that it receives a steady flow of power. While it is cheaper than the electric options, you need a compressor and a hose, so you should add those expenses to the price if you do not already have them.
Electric impact wrenches are the best option for the average person and DIYer, and they come in two versions: corded and cordless. Cordless wrenches are convenient because they are battery-powered, and compact, so you can keep one in your car in case you need to change a tire. However, they are more expensive, and their power output is lower than the corded ones.
There are other features besides the power source that you should consider. Torque rating is the measure of torque that the tool can deliver, and it is listed in foot/pounds (ft./lbs.). Some models include a switch with which you can control the different levels of torque. Keep in mind that most basic jobs require at least 200 foot-pounds. The speed of the wrench is measured in RPMs and some have a trigger that allows you to select the speed you need.

What is an impact socket?
Impact sockets are designed specifically to work with impact wrenches to provide more torque. While a regular socket will shatter under the repeated impact of the wrench’s hammer, an impact socket will withstand it with no issues. You can easily tell them apart because impact sockets have a black oxide coating that protects them against corrosion. It also ensures that the coating will not eventually chip off because of the tool’s vibration. Always make sure that you have the right impact socket for your impact wrench.
Conclusion
The right impact wrench can loosen even the toughest bolt of nut. Typically used in the automobile industry, this tool brings additional force and grip when no other wrench will work. Although similar in appearance, it should not be confused with the impact driver, which is used for drilling. Impact wrenches can be categorized into two basic groups: pneumatically or battery-powered. The former is better suited for heavy-duty tasks, whereas the latter is perfect for the average DIYer. Remember to always attach an impact socket to your wrench because it is specifically designed to withstand the power of this tool without breaking.