There are more than one ball joint on each front wheel assembly. There's one in the steering knuckle, for the forward thrust arm. Theres one include in the wishbone arm. There's one in the tie rod end. And technically there are two in the sway bar link.

The most likely one to cause problems is the wishbone or rear control arm ball joint. The forward thrust arm ball joint is also a possibility but in my experience it's only failed a third as much as the wishbone ball joint.

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2002 BMW X5 4.4i
Metallic Gray
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