Guys,

Just wanted to get confirmation of something I really didn't realize until I started a ball joint replacement project. I knew the ball joint was responsible for allowing the knuckle to rotate to turn the wheel while fixing it to the LCA and the chassis in general.

It's when I took things apart that I realized the castle nut alone essentially holds/attaches the ball joint stem to the LCA and it bears the load of the car's weight (car -> strut -> LCA -> ball joint -> knuckle/wheel). Am I understanding this correctly?

If so, it's amazing and scary to think that a little nut is holding the LCA/knuckle together. I have seen other cars where the ball joint is below the LCA and the castle nut is merely there to hold things together but not bear the load.

I'm sure this may be obvious for many of you... I just never looked beyond the rotors until now.

Thanks.

 

it's not just the nut that holds the balljoint "stem" in place.
that stem gets seized into the LCA.
plus the cotter pin makes sure that the castle nut doesn't loosen off.

 

Thanks for your response. I guess ultimately the stem getting seized into the LCA is what allows the ball joint to bear the load of the car. But initially, before it's seized, I see the weight of the car pushing down on the strut, which pushes down on the LCA, which pulls down on the ball joint stem via the castle nut. Since the stem tapers in such a way that the LCA could slip off if the nut wasn't there, I was a bit awed or surprised that design works. I'm sure the engineers designed it as such... just interesting to think a little castle nut is what keeps all that in place until the "seizing" occurs.