Ball Joints On My 73 Dart

Well the 73s were stronger than the 72s!
Your BJs are the same type and size, that came in the E-body Challengers/Cudas and the B-bodies. Those Joints supported Hemi's, and went 150mph.
Your helpful parkinglot-friend is neither helpful nor a friend.

If he wants to talk weak, he should be talking about the teensy spindles on the 9inch drum cars from 72 and older. That is the only weaklink I have seen.And really they do a fine job in the 6-cylinder cars that they came on. They don't all just give up either, the moment you put a 360 on them. But if you start stuffing them hard into corners with one, there's a pretty good chance, sooner or later,a wheel will be wheeling on down the road without you.I remember this one time... in about 1978 or 79........