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What is the difference between an automatic torque wrench and a click torque wrench?

Right now the 1/2inch torque wrench I use on my Jeep is a really cheep one I bought on amazon and it clicks when it reaches the set torque... Obviously this is a click torque wrench.

I am looking to get a 1/4 torque wrench now because I have built up quite the selection of 1/4 impact sockets and I would like to use them on my jeep since they are much nicer quality than my 1/2 inch sockets, and a 1/4 wrench can fit in many places a 1/2 wrench cannot. While searching around I have come across torque wrenches that are marketed as "automatic" but I am having trouble finding out how exactly they differ from a click torque wrench.

Do automatic torque wrenches stop have a clutch or something that prevents over torquing?

For all of you worried... I still plan to use my 1/2 sockets for lug nuts, spark plugs, and all of my nuts larger than 9/16 :)

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Good question, I have a wide variety of torque wrenches and torque screwdrivers, but have never even heard of an "automatic" torque wrench! –  Brian Knoblauch Apr 2 '13 at 12:16
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1 Answer

I think a click wrench is an automatic torque wrench. I think an automatic torque wrench is any wrench that stops applying torque once the specified torque is reached. This could be achieved in a number of ways. Whether it uses a clutch or spring and ball is irrelevant.

A click wrench will briefly stop applying torque once the specified torque is reached as long as you also stop torquing the wrench then you will have achieved the desired torque. So in this sense it is automatic.

The old style 2bar and meter torque wrench on the other hand is not automatic as you have to watch the gauge to know when to stop.

Use whatever gives an accurate torque rating (something that has been calibrated).

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