After breaking the stud on a badly needed 4 valve hydraulic stack, just really wanted to understand what happened. The calibrator indicated the release could be inhibited until a much higher torque value if pulled at a slow careful/gentle tug. The torque wrenches tested were 1 each Craftsman, 2 each ATD, and 2 each Pittsburg brands. Since then, any additional tests by others are not known to me.

What the test showed was for these click-release torque wrenches, a firm tug gave repeatable release results, a slow careful tug could be way beyond the desired effect. The bottom line is a firm tug is better than a slow tug.

The precision torque items today look at all the thread running torques from start up to free run to contact to seating values under computer and transducer control at a cost too way to expensive for any part-time mechanic. Stretch bolts and/or compressive steel gaskets usually are indicated with angular torque after contactin most auto mechanical venues, the Volvo D24T head gasket is torqued in this manner.