Power Tool
Impact Wrench
Impact wrenches are socket-driven fastening tools that deliver repeated rotational impacts for loosening or tightening nuts and bolts in higher-load applications.
Impact wrench drive sizes
Square-drive size affects socket compatibility and usually tracks the scale of work the tool is intended to handle. Actual torque depends on the specific model.
| Drive size | Typical role | Strengths | Tradeoffs |
|---|---|---|---|
| 3/8 inch | Compact automotive and assembly work | Smaller sockets and easier access | Less heavy-duty than larger drives |
| 1/2 inch | General automotive and workshop use | Broad socket availability | Larger than compact 3/8-inch tools |
| 3/4 inch | Heavy-duty fasteners and equipment | Suited to larger sockets and loads | Heavier for routine work |
| 1 inch | Very heavy equipment and industrial work | Large-drive capacity | Bulky and specialized |
Impact wrench vs. breaker bar vs. impact driver
Impact wrenches, breaker bars, and impact drivers can all turn fasteners, but they differ in drive interface, force delivery, control, and typical use.
| Tool | Interface | Typical use | Control |
|---|---|---|---|
| Impact wrench | Square drive and impact-rated sockets | Rapid loosening and tightening of nuts and bolts | Fast and powerful; final torque may still require a torque wrench |
| Breaker bar | Square drive and socket | Manual leverage for stubborn fasteners | Direct manual feel |
| Impact driver | Quick-change hex collet | Screws and lighter compatible fastening | Compact but not a substitute for socket-focused work |
Impact wrench applications
For fasteners with a specified final torque, follow the manufacturer procedure and use a calibrated torque wrench when required.
- Wheel and tire service
- Automotive repair
- Workshop assembly
- Heavy equipment with appropriate larger-drive tools
Impact wrench articles
Browse practical impact wrench articles covering drive sizes, torque, tool comparisons, automotive work, buying choices, and common fastening tasks.
Drive sizes and torque
Tool and brand comparisons
Breaker Bar Vs Impact Wrench: Which is Stronger?
Bauer Vs. Earthquake Impact Wrench: Face-to-Face Battle
Ryobi 1/2 Impact Wrench vs Milwaukee: Who Stands the Top?
