Changed both mine recently but getting self leveling error once in a while? Thoughts?

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My X5 - 2008 3.0 Alpine white - Dark Burl Walnut wood trim, Premium pkg, Technology pkg, Active ventilated seat package, rear seat entertainment, 3rd row, Aerodynamic kit, 22'" Ac Shnitzer Type II rims, 4.8 Exhaust tips, Wheel Arches, Silver kidney grills, Gp Thunder H8 & H11 Bulbs