Craftsman CMCF900B Review

Removing stubborn bolts and rusted fasteners by hand can turn a quick job into hours of frustration, sore muscles, and rounded-off heads that make the problem even worse. Whether you are swapping winter tyres in the driveway, working on a suspension overhaul under the bonnet, or assembling heavy machinery on a construction site, there comes a moment when a standard ratchet simply does not have enough breaking power to get the job done. That is where a cordless impact wrench changes everything — it delivers high-torque rotational blows that crack loose even the most seized nuts in seconds, without the hassle of an air compressor or a tangled hose. Modern battery-powered models now rival the performance of pneumatic tools while giving you the freedom to work anywhere, from the racetrack pit lane to a remote farm shed. If you have ever wasted an afternoon wrestling with a rusted axle nut or struggled to reach tight spots under a vehicle, investing in a capable impact wrench could be the single best decision you make for your toolkit this year.

When shopping for a cordless impact wrench, the first thing to look at is the maximum torque rating — measured in newton-metres (Nm) — because that number tells you exactly what the tool can and cannot handle. Compact models in the 200–300 Nm range are fine for light automotive work like wheel lug nuts, but if you plan to tackle rusted suspension bolts, crank pulleys, or heavy equipment fasteners, you will want something north of 400 Nm. Battery voltage is the other major factor: 18 V and 20 V platforms dominate the market, and choosing one that fits batteries you already own can save you a significant amount of money over time. Beyond raw power, pay attention to weight, grip comfort, LED lighting, and whether the tool comes as a bare unit or a full kit with battery and charger.

In this review we take a close look at a high-torque cordless impact wrench from a well-known American tool brand that has been trusted in garages and workshops for decades. We evaluate its real-world performance on rusted hardware, its build quality and ergonomics for all-day use, how it stacks up against competing models in its price bracket, and whether the bare-tool offering makes sense for buyers who are already invested in the brand's battery ecosystem. By the end, you will have a clear picture of whether this impact wrench deserves a spot in your tool collection.

At the heart of this impact wrench is a brushless motor that delivers up to 475 Nm (350 ft-lbs) of maximum tightening torque and an even higher breakaway rating for loosening seized fasteners. It runs on the 20 V lithium-ion battery platform and spins at up to 1,700 RPM with a variable-speed trigger that gives you precise control — from gently seating a bolt to hammering it home at full power. The ½-inch (12.7 mm) square drive with a hog-ring anvil makes socket changes quick and secure, and the tool is built around a steel-reinforced gear housing designed to survive drops and job-site abuse. With a weight of approximately 2.49 kg (5.49 lbs) without battery, it sits in the mid-range for high-torque cordless wrenches — heavy enough to feel substantial but not so heavy that it becomes tiring during extended use.

Craftsman has given this model a distinctive red-and-black housing with a rubber overmould grip that provides a secure hold even with greasy or gloved hands. The compact head design measures just under 200 mm from front to back, which helps when you need to squeeze into tight engine bays or between frame rails where a longer tool simply would not fit. A built-in LED work light illuminates the fastener area automatically when you pull the trigger — a feature that proves invaluable when working in dim wheel arches or under poorly lit vehicles. The forward/reverse switch is positioned for one-handed operation, and the tool features three speed settings plus a variable trigger so you can dial in exactly the right amount of force for the task at hand.

Day-to-day usability is where this impact wrench really earns its keep. The variable-speed trigger is smooth and responsive, letting you feather the power when starting a bolt before ramping up to full torque once the threads have engaged. The three electronic speed modes — roughly low, medium, and high — let you set a ceiling on RPM and torque output so you do not over-tighten sensitive fasteners or snap smaller bolts. The tool balances well in the hand with the centre of gravity sitting just behind the anvil, and the overmould grip absorbs vibration effectively during extended hammering sessions. The hog-ring anvil holds sockets firmly but releases them without excessive force when you need to swap sizes, striking a good balance between security and convenience.

This impact wrench is sold as a bare tool, meaning the battery and charger are not included — it is designed for users who already own compatible 20 V Craftsman batteries or who prefer to purchase them separately. The tool is compatible with the full Craftsman V20 battery range, from compact 1.5 Ah packs for weight-sensitive tasks up to high-capacity 5.0 Ah packs for maximum runtime during heavy demolition or assembly work. While the bare-tool format keeps the upfront cost lower, it is worth budgeting for at least one high-capacity battery if you plan on extended use — the 475 Nm motor draws significant current under full load. The steel-reinforced housing and tool-steel internal components speak to Craftsman's focus on durability, and the brand's reputation for standing behind its products adds peace of mind.

The tool measures approximately 190 mm in head length with an overall height of around 220 mm, making it one of the more compact options in the 475 Nm class. It carries Craftsman's standard limited warranty that covers defects in materials and workmanship. With a customer rating of 4.8 out of 5 stars across 505 reviews, users consistently praise its raw torque output, compact form factor for tight spaces, and the value it offers compared to premium brands charging twice the price. Common feedback highlights how well it handles lug nuts, axle nuts, and suspension hardware that previous impact wrenches could not budge, with several reviewers noting that it outperforms their expectations for a tool at this price point.

This high-torque cordless impact wrench is built for automotive enthusiasts, professional mechanics, and anyone who regularly faces rusted or over-torqued fasteners that need serious breaking power without being tethered to an air line.