BEVINSEE Polyurethane (Poly) Differential Mount Bushing Kit For BMW E46 Z4 E85 X3 E83. For BMW X3 Series E83 2003-2010. For BMW Z4 Series E85 2003-2008. The factory differential bushings are made of rubber and are very soft, especially if you drive higher mileage or drive aggressively, these bushings will wear out quickly.
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