Apparently nobody bothered to read this or follow the link so here it is again...... They remove the copper before shot-peening so it is done to all rods prior to heat treating so that only the bearing and pin holes get surfaced hardened from carburizing and the rest of the rod will bend before breaking.... Apparently some of the OEM rods skipped the removal process and or shot-peening. The proper way to size rods is simple and would be a lot cheaper than copper plating. Think about it. If the rods were "dipped" then the cap and rod mating surfaces would be covered too (defeating the purpose of adding metal)and still require machining which is the way to resize the rod anyway.....