Some folks might look at this and say, “I’ve already got a socket wrench” or “I’ve got plenty of ratchets (and I don’t need one that big).” But what makes the torque wrench stand out– and why you absolutely need to have one in your arsenal– is that it measures the precise amount of pressure you use to tighten down a nut or bolt. Why is that important? Because in certain situations (as with lug nuts and oil drain plugs) it’s important that the tightness is definite.
Many sub-assemblies of the car, such as the engine and transmission as well as the vehicle itself, are built to exact tolerances, and it’s up to the torque wrench to deliver that specific tolerance. It’s even more crucial with newer vehicles thanks to the advent of a lot of aluminum, soft metal and plastic parts on cars. The last thing you need is to strip or over-tighten. In fact, both under-torquing and over-torquing can have unfavorable consequences. For instance. under-torquing a wheel lug could result in the nut loosening and eventually falling off. Over-torquing a lug can actually weaken the wheel stud and cause it to crack and break which can lead to the same results. So, it’s obvious why every DIY mechanic should own a torque wrench.
Take the example of oil drain plugs and wheel lug nuts. Check the manual for the recommended torque. Set the torque setting on your wrench by twisting the handle to the desired settings. Listen for the click, which indicates you’ve reached your set torque, then stop.
Something else you should be aware of with your torque wrench. Never drop it or use it as a hammer. That’s a sure way to seriously mess up its calibration, which could seriously mess up whatever it is you’re torquing. When you are done using your torque wrench, back the torque all the way down before you store it away. That will help maintain the settings a lot longer.
To see the calibration and use of a torque wrench in action, check out the video below.
Harbor Freight carries a number of high quality torque wrenches at great, low prices. The Pittsburgh Pro 1/2″ Drive-Click Type Torque Wrench is a bestseller and one that Car Craft magazine endorsed as having “impressive accuracy” and “amazing value.” Check out these and other heavy-duty hand tools, all with a lifetime warranty.