PB blaster was the key when I did my ball joints. Soak them and let them sit then attack with a pickle fork and some taps from a small sledge. The first side took a bit of convincing but the one that sat longer with the PB came out pretty fast.

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2013 X5 xDrive3.5i Premium
2002 530I Sport Package
2001 X5 4.4i
2001 M3