Torque Thrust lug nut issue

that would worry me to death. I was in the passengers seat of a hotrod 65 ss Impala when she tossed the right rear Cragar. My head hit roof, then windshield, then from eblow up of me went out the door window. The car was hurt much more than I was. 2nd wheel well formed in that quarter panel.
My best guess, based on previous posts in this forum, your wheels have a metric hole circle that doesn't quite match the 4.5 inch lug circle.