Posted by Ron L on May 26, 1999 at 13:45:51:
In Reply to: Lug Nut Torque posted by John Morrelles on May 19, 1999 at 14:56:34:
I'd agree that the torque sticks are fairly accurate. Discount Tire in the Detroit area advertises that they use first a torque stick and then an actual torque wrench.
From how the tire store described the torque sticks to me (sorry, I'm not a metallurgist and I hope I get the description correct). Since an air wrench operates with a bit of a hammering type of action, the torque sticks are designed to flex or twist against the torque rating. Every time the air wrench "hits", the torque stick merely twists because the lug is at the correct torque spec. They explained that if a breaker bar was attached to the torque stick, it would be easy to see the twist. Also, if a breaker bar was attached, it would be possible to twist the stick more than was intended and over-torque the lugs.
Hope that helps.