Does anyone know the size of the upper ball joint nut? The one that actually holds it to the knuckle, not the 4 small ones to mount it to the control arm. I damaged mine and need to replace it, but don't need a whole new ball joint. According to this page it's a 7/16-16 but that doesn't even seem to be a valid size/thread pitch, at least nothing that I can find. Oddly, this nut is also absent on the DMCH exploded parts diagrams.
Also odd is that the front end service bulletin document (SC-01-11/81) seems to suggest that both upper and lower joints use the same nut (SP10179) but on my car the lower ball joint is definitely larger than the upper.
Service Bulletin SC-04-11/81 may explain some of this. It seems to suggest that some cars have lower ball joints with a larger diameter than the uppers. I have an early car, 1561, could this explain the discrepancy?
Color me confused, can anyone shed some light on all this?
Todd