Originally Posted by
MattW
Does anyone know the reason for using a composite ball in the lower wishbone, but a steel in the upper?
Also, does anyone have any spares of the balls they could measure for me? Interested to check if they are a true 6mm OD, and what diameter is the king pin?
Steel balls are usually tighter tolerences so they often produce less unwanted play or slop. But the kingpins usually slide smoother thru a nylon ball, so they are often used in the lower arm, where the smooth sliding action is a bit more important than the tightest fit.