Hey Lud, ...... I didn't even realize that my comments can be construed to be directed to you, and even then, why get so defensive ........ and surely when we post here we are posting based on our opinions or perogratives or whatever .......... you make good points ........ but the gist of my comment was to point that we seem to be missing the basic built in error of the instrument (unless TireRack's was superior) ....... and I did use a wink so people get a hint .......!
.......... let me help you out. I understand your "real life" example but you are missing the point regarding what a reported error means.
An error of +/- 4% means the error can be either off by as much as +4% or -4% at ANY given time. And, This error is a "random error" and not necessarily fixed as you assume. Thus if on one lug nut it errs +4%, it can very easily err -4% on the next lug nut just because that is the "standard deviation" in the calibration; and since this is "random," the difference between the two acn be as high as 8%. For it to err ALL the time at either +4% or -4% consistently is like saying how many times can you get heads tossing a coin. If the error is unidirectional, they could have easily stated the error will be either up to +4% always or down to -4% always on ALL lug nuts. They didn't. So either (a) they are not to savvy to make that distinction, or (b) they deliberately did not say so because it ain't so.
Now, will I still buy a torque wrench that has +/-4% error, yes. Will I pay $89 for one that does the same thing for $19, no. Do I care if one lug nut is 8% off than the other? If my worries are to this level when I am out their driving/tracking the car, then I have must be in the wrong business.
YMMV
