Since the joint of the control arm (the joint connects the control arm and the rotor) is loosen, so that the wheel shakes when you push the wheel by holding at the point of 3 o'clock and 9 o'clock. The sympton is that when you drive your X at about 120 KM/H, your steering wheel shakes and especially when you push your brake at that speed. Also you feel the steering wheel shakes when you are cornering at high speed. The BMW service center told me that the control arm must be changed.

Thanks Alpac, so I just need to screw the nut by using the wrench to push the joint out, right?

One more thing, I just bought the control arm made by Febi Germany, anyone heard about the manufacturer? How is the quality? Thanks for comments!

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--2004 E53 X5 4.8is - ECE version; right hand drive; Located in Hong Kong; ext. black sapphire metallic; int. leather black; adaptive dynamic bi-xenon headlights; 16:9 onboard monitor w/o navigation; 20" genuine BMW Y-spoke 214 wheels with Bridgestone Dueler H/P Sport tires; Int. rear view mirror w/ compass.