<font color="blue"> FYI, in general, grade 70 chains are not rated for overhead lifting - most manufacturers recommend grade 80 or 100 for that. </font>
Small point, and correct me if I am wrong on this, but my understanding is that there is a difference between "overhead" and "vertical" lifting.
Vertical lifts would be picking something up, which we all do when we use the chain hooks on our loader to lift something.
Overhead lifting relates to using chain with cranes that lift loads over equipment, buildings and so on.
Doesn't matter where the chain is made, grade 70 should never be used for overhead lifting, but it should be just fine for use in any direction (within grade 70 design limits) when hooked to our tractors.
<font color="blue">I would use what I call a margin of ignorance. Since you don't know exactly how strong the chain REALLY is, buy the next size up for an extra margin of safety. </font>
Keeney's chain rule of thumb...works for me! /forums/images/graemlins/grin.gif