Everyone that’s ever worked on a car understands the importance of the right tool for the job – or even more pertinent, not having the right tool for the job. How many times have you battled to undo that last obstinate bolt? In situations like this handheld, ratchet wrenches are just not up to the task. This is when you need the best impact wrench, driving the appropriate impact socket, to undo stubbornly seized fasteners, easily and without personal injury.
A cordless, pneumatic (air or gas), or even wired/ corded impact wrench, is the answer to undoing troublesome nuts and bolts, and also for rapidly tightening bolts or screws. Not only will the best impact wrench save you time, but it could save you the cost of having to get a professional engineering company to remove a bolt or nut that has been “rounded” because you used a handheld ratchet wrench and normal socket to try and undo a seized fastener.
After reviewing many of the products on the market, we recommend these three impact wrenches above.
Review Of The Best Power Impact Wrenches
DeWalt’s MAX XR impact wrench is powerful and carries the company’s reputation for reliability. The DCF899P1 cordless impact wrench is the perfect tool for undoing stubborn fasteners or saving time running up nuts. Its brushless motor, powered by a 5 AH battery, delivers a healthy 700 foot-pounds of torque with a breakaway of 1,200 foot-pounds; enough to take care of the most demanding jobs without overheating. The three-speed selector switch allows you to select the best speed for the job, while the built-in LED work light allows you to carry on working even if the sun goes down. What’s more, measuring a mere 8-13/16 inches in length and weighing just 7.2 lbs, the DeWalt cordless impact wrench can get to those difficult-to-reach fasteners you often come across in cars.
If you’ve ever worked on heavy-duty trucks that spend their life on (often) salt laced roads, you’ll know that rusty and seized bolts can turn even the easiest job into a frustrating nightmare: Not if you’ve got a Milwaukee 2767-20 automotive cordless impact wrench. Its 1400 foot-pounds of reverse torque is enough to crack free even the most stubborn undercarriage fasteners. And to make the job even easier, the “Bolt Removal” mode slows the speed to 750 RPM once the hold has been broken, giving a smooth finish to the task. Delivering this sort of power you could be forgiven for expecting a bulky power tool. Not so. Weighing only 7.5 pounds and measuring 9.4 x 4.2 x 11.8 inches, this tool is compact. And of course, coming with not one, but two Li-ion batteries and a charger means you will never run out of power.
The AIRCAT 1150 is a highly rated, light, but powerful ½-inch air impact wrench. Its ergonomic design allows you to hold it like a gun, while, spinning at 9,000 RPM, the variable speed pneumatic motor produces 900 feet-pounds of maximum torque and 1,295 feet-pounds of reverse torque. At the same time, housed in a corrosion-free, black powder-coated casing, the hard-hitting twin-hammers deliver 1,400 impacts per minute. And all of this performance is achieved with a sound level of only 86 decibels, thanks to the AIRCAT’s patented tuned exhaust muffler technology, which allows discharged air to pass without developing back pressure, thus retaining more power, and significantly reducing noise. Considering the performance, and looking at the specs you would probably think this air impact wrench will set you back an arm and a leg. Wrong: It’s one of the best-priced impact wrenches on the market.
This professional impact air wrench NiTROCAT 1250-K is recommended for use in automotive repair shops and service stations. This is also due to the fact that the service station already has a compressor, so you do not have to buy it separately. The small size and weight makes it easy to tighten or loosen screws in places with limited access. The dual impact mechanism allows you to achieve high torque up to 1,300 ft-lb with little need for compressed air while providing a highly durable product. Ideal for tire work as well as truck and machinery repairs. It has a reverse function and an ergonomic handgrip, making it comfortable and safe to work with. The noise level is limited to 86 dB, which is pretty low for this kind of equipment, and the anvil is a standard 1/2″ size that fits many impact sockets of your choice. For an impact wrench like the Nitrocat 1250-K, only sockets made of a special alloy should be used
With so many types and brands of impact wrench on the market, it’s extremely difficult to choose the right one. So to simplify the process we’ve put together a guide to help you make an informed choice when selecting the best impact wrench for your application.
The Different Types Of Impact Wrenches
There is a wide assortment of good impact wrenches on the market, all with unique features, advantages and disadvantages, and all offering the impact power that handheld ratchet wrenches can never deliver.
Wired/ corded electrical impact wrenches
These require an AC outlet and are therefore not truly portable. In most cases, they are also not as powerful as those powered by compressed air. However, they are more compact than self-powered units and often offer better costing than pneumatic wrenches.
Compressed air impact wrenches
The main benefits of the pneumatic impact wrench are its weight and power. There are also two types of air impact wrenches: Inline air impact wrenches and those equipped with a “pistol” grip. Like wired wrenches, these can be quite compact, although they too require an external power source of compressed air.
Cordless compressed air impact wrenches
Although not common, these work by using CO2 or compressed air in a canister. They are best suited to emergencies because of their limited power supply.
Battery-powered cordless impact wrenches
Early cordless impact wrenches struggled with low torque, restricted operating time and the short battery life of the NiCads. And of course, they were expensive. Modern battery-powered impact wrenches with Li-Ion (Lithium-Ion) batteries, however, have good torque and Impacts Per Minute (IPM), are lighter, and still easy to use. Their greatest advantage is their portability. So much so, that they have become an essential part of field tool kits and even car and truck toolboxes.
When evaluating the many impact wrenches in the marketplace, you will find that manufacturers offer a variety of features.
What Key Features And Brands To Look Out for When Buying the Best Impact Wrench?
Irrespective of the type of impact wrench you decide on, the following features/specifications are important:
The output power
When it comes to impact wrenches, irrespective of their type, the key to their functionality lies with the “motor” – electric or pneumatic. This performance is measured by:
- The Torque Output. This is an indication of how “strong” the twisting effect will be to loosen or tighten fasteners.
- The Impacts Per Minute. Denotes how many times the tool will impact the offending part per minute. Higher is better.
The theory behind the effects of speed (RPM) and torque on impact wrench performance states that at high RPM, the inertia of the rotating parts of the tool causes an overshoot of the actually claimed torque. Thus, the slower the tool rotates at the final rundown, the better the control is. However, in everyday use, this is very academic, with torque being the overriding factor.
On electrically powered motors make sure the motor is brushless. This requires less maintenance.
Battery type and capacity
For portable battery-powered impact wrenches this feature is critical. The best battery is a Li-ion. Although slightly more expensive than NiCad, it is lighter, more powerful and extremely compact. It will also hold a charge much longer with better battery life.
Electronic assistance and smart controls
Assist modes and smart controls are handy-to-have features for impact wrenches. Most fasteners have a torque rating – especially those performing critical functions – that is easy to overshoot. Having a pre-set stop allows you to quickly run a nut or bolt to a predetermined point, then carry out the final torque by hand. In reverse, the auto mode allows you to undo a fastener and stop or slow down before it comes off.
Most impact wrenches will have a stylized grip – typically rubber, or another soft material that allows for comfortable and safe control of the wrench.
Although the power of the impact wrench largely determines the size of the tool, you should think of those unforeseen occasions where you might need to work in a confined space. Thus, always consider how big the wrench is, including the battery or gas canister.
A critical, less tangible feature that often does not appear on the packaging is how reliable the manufacturer is. Brands are built over many years, by supplying quality, reliable products to customers. Thus, the best way to ensure that the product lives up to the claims is to stick with brands whose manufacturers have built up a solid reputation for delivering on their promises.
The Best Power Impact Wrench Brands
These brands have a solid reputation for delivering quality products:
DeWalt. The Maryland-based DeWalt Company is internationally known for its high-quality power tools. Founded in 1924, the company produces equipment for construction, home improvement, and manufacturing. And adorned in the company’s bright DeWalt-yellow it is hard to miss their impact wrenches.
AIRCAT. Founded in 1998, this American company’s pneumatic power tools boast substantially reduced noise levels while retaining more power and torque than most of their competitors. This is achieved through AIRCAT’s patented tuned exhaust muffler technology that allows discharged air to pass without building up back pressure, thereby reducing noise and maintaining power. AIRCAT is also known for its patented ergonomically engineered grip design that overcomes stress and fatigue during operation.
Milwaukee Tool. Established in 1924, Milwaukee Tool has led the industry with a range of professional construction tools since its inception. More recently, acquired by Techtronic Industries Co. in 2005, the company has built up a reputation for its heavy-duty and high-performing power and hand tools, including its impact wrenches. The first to develop lithium-ion technology for power tool applications, the company continues to deliver innovative and advanced technologies in electronic, battery, and brushless motor equipment.
Makita Corporation. It is a manufacturer of high-quality power tools and is one of the most respected brands in the global market. Established in Japan in 1915, as an electric motor manufacturer, becoming the first brand in Japan to produce portable electric planers in 1958. A year later, the firm started the development of its own line of power tools, before finally launching a rechargeable battery-powered drill – the 6500D in 1969. The company continued its innovative development and in 2005, introduced the TD130D, its first lithium-ion battery power tool. Today this technological innovation can be found in its range of impact wrenches, sold in more than 40 countries around the world.
Ingersoll Rand. Ingersoll Rand Inc., founded in 1859, is an American-based manufacturer of industrial equipment, technologies and related parts across a family of brands. The company has over 30 manufacturing facilities located in the Americas, Europe, the Middle East, and Asia Pacific with offices in 35 different countries. The company, best known for its range of rotary screw, reciprocating and sliding vane compressors, is equally adept at producing high-quality battery-operated power tools such as the 20 V, W7150 ½-inch drive, high-torque impact wrench.
Ryobi Tools. It is a brand that falls under the Ryobi Limited brand that first opened its doors in 1943. Through innovation and continuous improvement, Ryobi has developed a brand well-known for its high-quality electric power tools. Ryobi Power Tools, which is actually a brand of Techtronic Industries, but licensed to Ryobi Limited, operates a number of manufacturing plants with 12 facilities spread over six countries. The company has been operating a single American manufacturing plant in Shelbyville, Indiana.
After reading the guide to selecting the best impact wrench you may still have one or two unanswered questions, so we’ve included a few frequently asked questions below.
While impact wrenches can be used to save time on tightening and loosening bolts and nuts, their primary value in automotive applications is undoing seized fasteners that a normal hand-held ratchet wrench cannot budge.
It’s important to always wear safety glasses with side protectors when using an impact wrench. Make sure you’re not wearing any lose clothing or accessories such as a tie, or a watch – these could become entangled with the socket drive. When using an air-impact wrench you always need to wear hearing protection – an air-impact wrench generates noise levels of up to about 103 db.
Having worked through this guide and taken heed of our product recommendations, you should never have to worry about dealing with seized bolts and nuts again. And no more grazed knuckles.
While the exact requirements will vary depending on the type of air impact wrench, you would typically need an air compressor with 4 to 5 CFM at 90 PSI to run a 1/2 inch impact wrench. This should have a 20-gallon reservoir to ensure flexible and uninterrupted operation.
For safety you must always use an impact socket. These are easily identified by their matt black finish and the cross-hole, in the handle end, that engages with the retaining pin and ring, or locking pin anvil on the impact wrench. These sockets are thick walled and made from molybdenum chromium steel so that they do not shatter when in use.
The higher the power (torque) output the higher the voltage required. You will find that manufacturers equip their powerful impact wrenches with higher voltage batteries. A high power tool with a low voltage battery will have a very short operating time with restricted power delivery. Follow the manufacturer’s instructions on this.
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