ball joint separator

[RichardJ]

I don't really care for the hammer method as most guys use. If a spreader or pickle fork doesn't work, I use a hammer, but only in conjunction a bucking hammer or bucking bar on the back side.
I use the largest hammer head or chunk of iron I can fit on the back side of the knuckle. The mass behind the knuckle keeps everything from moving and increases the shock of the hammer I'm striking against the front.