That clip keeps the ball joint in there. The dust shield is held on separately by being squeezed on. The clip must go once you have the hub separated from the control arm/ball joint.
If you don't have a 15+ pound sledge, definitely get one. The pickle fork works by applying strong lateral force. Do not try to wiggle it up or down, it wont do anything but bend the pickle fork. Wail on that thing like 10 times in a row really hard, and POP. It'll separate.
Sorry I completely forgot about the whole pickle fork thing. It's been august since I last did this
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