Cooling System O-Ring Set Kit BMW X3 X5 2.0 2.5 3.0 4.4 4.6 4.8 Radiator Hose

I would also suggest you order a new coolant bleeder screw (BMW Part #17111712788). Finally, do not overfill your cooling system as this will prevent the cap from venting excess pressure. After bleeding the system, siphon out excess coolant until the level is at the upper mark.

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