Securely Fasten Nuts and Bolts Using the Best Torque Wrench
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Mountain Torque Wrench -
K-Tool International Torque Wrench -
Sunex Tools Torque Wrench -
TEKTON 1/4 Inch Drive Click Torque Wrench -
CDI Torque 2503CF3, 1/2” Drive Computorque 3 Electronic Torque Wrench -
GEARWRENCH 1/2inch Drive Electronic Torque Wrench -
Snap-On QCE325A Electrotork 1/2” Drive 25-250 Ft/lb Torque Wrench -
Precision Instruments C3FR250F, 1/2” Drive Split-beam Click Wrench -
Park Tool Ratcheting Click Type TW-6 Torque Wrench
Torque wrenches are precision instruments, used to ensure that nuts and bolts are properly tightened in automotive engines, aviation and industrial applications. They provide a means of measuring the amount of force applied to the fastener, in order to tighten it. Without this measurement, there is no sure way of verifying that these fasteners have been properly tightened.
If you’ve ever tightened up something just finger tight on your car engine and then forgotten about it; you probably have experienced the bolt or nut loosen up fairly quickly when the car was started. Since there is no opposing force to cause the nut or bolt to remain tightened, it is easy for it to become loose. However, a properly tightened bolt or nut won’t come loose, even after many hours of operation.
The way that nuts and bolts work is that when tightened they put pressure, called “clamping force,” on the items they are holding together. As those items are more massive than the hardware holding them together, they push back, actually stretching the bolt microscopically. It is this stretching which prevents the bolt from coming loose. The stretching is like stretching a spring, allowing the bolt head and the nut to maintain pressure on the sides of whatever they are holding.
There is a strong element of friction involved in fastener holding power. The friction between the head of the bolt or the side of the nut and the object they are holding, prevent the bolt head or nut from turning. As long as there is enough clamping force to maintain that friction, they won’t budge.
While tightening fasteners to the proper torque is the way that we ensure that there is enough clamping force, this clamping force can change due to the type of finish on the fasteners and whether or not the fasteners have been previously used. The threads of a nut and bolt pair which has been tightened and loosened a number of times (without rusting) become somewhat polished by the pressure. This will increase the amount of clamping force applied each time, if tightened to the same torque.
Nevertheless, the torque values which are used for nuts and bolts take into account the type of material used in the fastener, the hardness of that material and any surface coating. Engineers use pre-calculated tables, which take all of those factors into account, when specifying the proper torque to be used.
Most torque wrenches today are “click type” wrenches, meaning that they make an audible click when the fastener is tightened to a pre-determined torque. The torque desired can be set electronically, with a mechanical digital readout or with a vernier, depending upon the design of the torque wrench. Generally speaking, the electronic ones are considered the best, as they are the easiest to set and work with. Vernier calipers require knowing how to work with a vernier.
Torque wrenches which have a dial or needle and gauge aren’t really torque wrenches, but rather torque meters. While it is possible to use them to tighten a fastener to the right torque value, it is extremely hard to do so accurately.
Torque is measured in foot-pounds or inch-pounds. Conversion from foot-pounds to inch-pounds is simple; all you have to do is multiply the foot-pounds by 12. One foot pound is one pound of pressure applied over a lever, where the force is applied one foot form the fulcrum or rotational point. So, if you have two torque wrenches, one that is one foot long and the other that is two feet long, and apply the same amount of pressure, the actual torque would be different. That one pound of force would become two ft-lbs of torque with the two foot long torque wrench.
When selecting a torque wrench, it is important to verify that he tool will cover the entire torque range that you will be setting. A torque wrench that has a maximum torque value of 120 ft-lbs. won’t do you a bit of good, if you have to torque a nut to 150 ft-lbs. Having all torque ranges you need may require having more than one torque wrench, although it is possible to get one torque wrench which will cover all needed torque values for working on a car engine. Check out our list of the best torque wrenches in 2022.
Tighten up your projects perfectly with these amazing torque wrenches
Mountain Torque Wrench - Best Torque Wrench Overall
For a low cost torque wrench, this one has an amazing range; allowing you to set torques up to 250 foot-pounds. That’s 100 foot-pounds higher than any of the other torque wrenches on this list; which is why I feel it deserves the top spot. It’s 25 inches long, making it slightly longer than the others; but you need that extra length for the higher torque values. The ratcheting head makes it easy to use it in tight places. It comes in a blow molded case for easier storage and to protect the tool.
K-Tool International Torque Wrench - Honorable Mention
K-Tool, sometimes known as Kool Tool provides another option in micrometer torque wrenches. This is a very common wrench to find available at local auto parts stores. Like most micrometer torque wrenches, it clicks when the proper torque is achieved. This torque wrench has a 1/2 inch drive ratcheting head. It can be used over a range of 10-150 foot-pounds.
Sunex Tools Torque Wrench - Consider
Sunex brags that this torque wrench is calibrated to plus or minus 3% of torque accuracy, which actually makes it more accurate than the Craftsman. Of all my picks this is the only one which states this in their specifications; all the other manufacturers rate their tools at plus or minus 4%. The ratchet gears are CR-MO steel for long life. This wrench provides a torque range of 10-150 ft. lbs. Comes in a blow molded case.
TEKTON 1/4 Inch Drive Click Torque Wrench - Best Budget Torque Wrench
MIT, sometimes sold under the brand name “Tekton” provides a nice torque wrench kit. I say kit because it is the only torque wrench I have seen that comes with 5” extension and a 1/2-inch to 3/8-inch drive adapter. This saves you a couple of bucks in not having to go out and buy your own to use the torque wrench with 3/8-inch drive sockets. The micrometer torque adjustment is locking, so that you don’t have to worry about it moving when you adjust it. The torque range for this wrench is 20-150 foot-pounds.
CDI Torque 2503CF3, 1/2” Drive Computorque 3 Electronic Torque Wrench - Best Torque Wrench Overall
CDI Torque is a company that specializes in torque wrenches, torque measurement equipment and torque calibrators. This is one of their top wrenches, although I must confess they have one line thats even more expensive than these. The wrench has a flex ratcheting head which allows you to have the wrench as much as 15 degrees off of true, without affecting the torque value. It is a digital model, with push button controls. The controls remember the last torque used, so that you dont have to reset it. A three LED system as well as an audio alarm lets you know when you are getting close to the right torque, as well as when you have overtorqued. It can be used for a range of torques up to 250 ft/lbs. the tool is 27 inches long.
GEARWRENCH 1/2inch Drive Electronic Torque Wrench - Best Torque Wrench Overall
GearWrench is the same company that really made ratcheting box end wrenches popular. This torque wrench is a dream to work with. The digital readout has three LEDs, like the CDI unit, as well as an audio tone. The gear head is low profile and swivels for hard-to-reach areas. The 60 tooth gear allows a 6 inch ratcheting arc. This tool will set torques from 25 to 250 ft/lbs. It is 26.5 inches long.
Snap-On QCE325A Electrotork 1/2” Drive 25-250 Ft/lb Torque Wrench - Best Torque Wrench Overall
Snap-on makes the best mechanics tools available anywhere. I have to include this torque wrench in that. This is a digital torque wrench, which maintains its accuracy for both right-hand and left-hand thread, regardless of handhold position. That can cause problems for a lot of torque wrenches. It can be used over a range of 25 to 250 ft/lbs at increments of .1 ft/lb. the membrane control panel makes it easy to set and LEDs as well as an audio tone let you know when youve reached the set torque. Overall length is 21.5 inches.
Precision Instruments C3FR250F, 1/2” Drive Split-beam Click Wrench - Best Torque Wrench Overall
This is a split-beam wrench, which makes it extremely easy to work with. The mechanism is not under any load, so there is no reason to reset it to zero after each use. That also makes it possible to adjust it with only fingertip force. It adjusts through a range of 40 to 250 ft/lbs in 5 ft/lb increments. An audio indication lets you know when youve reached the right amount of torque. Like the others weve looked at, this wrench has a flex ratchet head. The overall length is 19 inches.
Park Tool Ratcheting Click Type TW-6 Torque Wrench - Best Torque Wrench Overall
This is the only 3/8 drive wrench I've included on this list; all the others are 1/2 drive. However, with todays lightweight components, there are times when a lightweight torque wrench is needed. This wrench covers a range of 115 to 530 in/lbs (9.5 to 44 ft/lbs). A dial is used to set the desired torque value. When the proper torque is reached, it is indicated by a click sound. It works for both right-hand and left-hand threaded fasteners. The tool is 15 inches long.
