It is not the same shift. I verified that.
When you get right down to it - it doesn't really matter WHY these have been peened. What matters is that all documentation that has been found so far indicates that the C should be there.
Little sidebar for you.
I am a shift supervisor in my 23rd year. No not for an axle plant or for a vehicle assembly plant, but for an outfit that produces products every day. These products are to be produced in a specific format. If inconsistencies develop from one shift to the next, those are addressed immediately. That means in a day or two, typically at shift change. If it can't be handled that way, then higher level management is brought in and it is fixed in less than a week. If another shift is making work for me, by producing products out of tolerance or format, that doesn't make me happy.
Let's say though that in this axle case that someone continues to put an extra C stamped on something that I don't think belongs there. If it keeps happening, I am going to develop a tool for a "one and done" fix to get rid of that C. What we have seen in these peened cases are multiple strikes and not using the same tool. For a production line, that doesn't make sense. Consistency is important and time is money. I don't think it happened at the axle plant.
It also does not make sense that it happened with vehicle assembly. Axles were labeled with tags on the end of the brake drums or in other ways. It was not necessary to look at the stamping on components as cars were being put together.
This anomaly went on from about mid August through the end of 69 model year production - about 2 months. In the real world, it does not make sense.
I might ask JohnZ what he thinks about this topic.
