Best Torque Wrenches For 2023

What is torque?

Torque refers to the amount of twist on an object like a nut or bolt. In the United States, torque is measured in units of foot-pounds (foot-pounds). If you weigh 150 pounds and stand on the end of a two-foot wrench attached to a lug nut, you’d deliver 300 foot-pounds of torque. Many lug nuts have an 80 ft-lb torque specification, so they can be tightened properly by, for example, hanging an 80-lb weight on the end of a 1-foot wrench. Most people don’t keep calibrated 80-lb weights in their garage, so they use torque wrenches. (Foot-pounds are also a measure of engine power, more important to many than horsepower that provides the oomph that gets a car rolling.) 

What is a torque wrench?

A torque wrench is a wrench that delivers a pre-set amount of torque to a fastener, and tells the user when it’s reached that value. To do this, it uses one of three primary methods. “Beam” torque wrenches employ a simple pointer on a scale. The downside is that you have to look straight at the pointer and scale to read the torque value, which is difficult while, say, tightening a wheel. Beam wrenches are still available, but they have largely been supplanted by click-stop wrenches which use an internal spring, ball, and detent. When the specified torque has been reached, the ball pops out of its detent, and a sharp “click” in the handle is felt. Electronic wrenches instead use a strain gauge and report the arrival of the target torque via vibration, beep, indicator lights, or all three.

What size torque wrench do I need?

Torque wrenches are primarily referred to by the socket drive size. Like ratchet wrenches, they come in 1/4-inch, 3/8-inch, 1/2-inch and 3/4-inch drives. The bigger the drive and the longer the handle, the more torque they can deliver. Most home mechanics will find that a torque wrench with a 1/2-inch drive and at least an 18-inch handle is the best choice for lug nuts, cylinder heads, suspension bushings, and other likely uses. If you’re rebuilding an engine, a 3/8-inch drive wrench is a better size for rod and main bearing end caps, but its shorter handle isn’t optimal for delivering torque to truck lug nuts, trailer hitches, or other high-torque fasteners. Fine assembly work such as small fasteners on critical pulleys, or compression of cork gaskets on finicky vintage cars, may require a 1/8-inch torque wrench for accurate low-torque delivery.

How to you maintain a torque wrench?

On click-style wrenches, it’s important that, after using it, the torque setting be turned down to relive tension on the internal spring. The calibration of most click-style wrenches is claimed to be good for 5,000 clicks. It’s also important that the wrench not be dropped. Torque wrenches can be recalibrated, but the cost usually exceeds that of a consumer-grade wrench. If you have questions about a wrench’s accuracy, an effective method is to test it against another torque wrench.

Do I need to calibrate my torque wrench?

The short answer is yes. Most experts agree that a torque wrench should be calibrated once a year, or after 5,000 cycles or uses. Sooner, if it’s regularly used in temperature extremes or if it has been dropped. 

That said, most consumers will will never go through 5,000 cycles if they’re only working on their own vehicle. Furthermore, sending a consumer-grade torque wrench away to a lab to be calibrated may be more expensive than simply replacing the old wrench with a new one.

Do I need anything else?

Nearly all torque wrenches are ratchet handles, so you need a set of sockets to go with them. If the wrench has a 1/2-inch drive, you need 1/2-inch sockets. An extension is sometimes needed to reach a lug nut without having the wrench scrape against the wheel or tire. Drive adapters can be employed to use, for example, 3/8-inch sockets on a 1/2-inch drive torque wrench, but the higher the torque, the better it is that the drive sizes of the wrench and socket match. If you are replacing a cylinder head, certain head gaskets require an “angle torque” method where you torque each fastener to a specific value, then tighten it further by rotating it a specific amount (e.g., 90 degrees). Some high-end digital torque wrenches have this functionality built in, but for others, an inexpensive torque angle gauge is necessary.