[Mike V. Florida]

Let me add this to the mix. The value on the charts are max values (well usually 75% of proof). They are not necessarily the values needed for a specific job. Let's take the 100lbs rear axle torque, since Ford did not use torque values during assemble of the Model A, where did this number come from?

Again as mentioned by a couple of people above strength is not the same as hardness. A diamond nut would not torque down the same a a steel nut.