The reason I ask is that a few years back I had a shop re-arch my springs. Unbeknown to me they used air hammer with a taper chisel instead of a press when removing the bushing scoring the inside of the eyelet. That scoring let water in between the bushing and eyelet rusting and eventually snapping along the scoring; straight line as you have pictured. The same shop did the same thing to a couple of other guys I know and the same failure happened to them in the exact same way.
Lazy MF’ers.
Did you buy the truck new?
Do you have a picture of the broken off part?