When replacing lower ball joints, should I go ahead and do the upper ball joint/control arms as well?

2000 F150 4x4

 

I don't. Lower ball joints tend to die before the uppers. Obviously check them to make sure they aren't loose, torn boots, etc, but I usually just do lowers.

 

This is what I do as well, well I do them in matching sets. So if an upper goes bad I replace both uppers and if a lower goes bad I replace both lowers. But I only do all 4 if the other set needs it from being damaged.

 

Both my upper and lowers were dead. If they move around like they just don't care, time to replace them.