how do these work??

http://www.harborfreight.com/cpi/cta...emnumber=42478

 

they work great

basicly they deflect a little bit at a certian torque load. that small deflection absorbs energy that would otherwise turn the lugnut.

 

The shaft diameter is the regulating factor. Notice in the picture that the right side is thicker then the far left one?

 

so how do you know when to stop?? do you notice it bend or does it force the wrench to stop??

 

Once the torque setting is reached the Torque socket will dampen or absorb the excess torque from the impact wrench like oldhalftons stated. There's an instruction sheet that comes with it that shows how to calibrate your impacts output. They are very easy to use.

 

Torque sticks will put you close enough for wheels, but they are not accurate enough for engine work. They work on a flex principal, like TRYING to break a rusted bolt with an impact and 12" extention. the extention "twists" absorbing the torque. Greg

 

Every tire shop I have worked at used them. You can tell when it's done, it stops spinning and the note of the gun changes a bit.

 

I don't think I change enough tires off too spend $70 ....

 

On the other hand - my flatbed has a dually rear end with eight lugs per side.

And I ended up going back over the torque on those lugs about four times each before they all read close to each other. (plus retorqueing after taking it down the road).

I wonder if they sell them singly...

 

That would make more sense for those of us that only change tires once in a while .

 

Off the big three tool truks you can get them singly.about $30-$40 I've got the 140lb to use at work(E450 vans), use it mostly to prevent overtightening then go over again with torque wrench.