Haha, I have not heard that term since school - free body diagram.
Check my logic here, I also think some people are saying the same thing in different ways and others are thinking on another page:
Take the 2500lb Z car.......going 70mph.....slam on the brakes, at that moment let us all try to agree on what is taking place. The nose of the car takes a dive. What are the G forces there? I think we can agree that all of the natural forces due + braking is not in a perfectly vertical line. Forget the calipers for a second, would it be correct to say that the top load lets say the strut mounts is trying to rotate anit clockwise from the contact patch of tire on the ground? Some of the cars forces (80%)? will be absorbed by the spring/strut but where does the rest of those forces go. Some I believe has to be translated through the T/C rod.
In my minds eye, the T/C rod is compressed and twisted during hard braking. After a few cycles of that well we see what happens. I am not sure if we can put #s on the loads but design here has a major part to do with the failure. I have not been around Z cars for yrs and yrs and yrs but do any of you older guys have pics of failed NISSAN STOCK t/c rods or front control arms? Kinda interested to know what they ran back in the day.