Sometimes even new tires can be defective and I've certainly heard of that happening more than a few times. Sometimes it helps to remount and rebalance the tires - spinning the tire on the wheel 180 degrees before rebalancing. You can also try taking a look at the balance of the wheels without the tires mounted just to see how "good" they are without tires. Are your wheels OEM BMW wheels? Also, is your X aging? Could it be a control arm problem? Just a few thoughts... GL!

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'08 335i Coupe - Barbera Red / Saddle Leather / Light Poplar Wood / 6spd Manual
Options: Sport, Premium, Cold Weather, Comfort Access, Active Steering (awesome!), Power Rear Shade, IPod Adapter, Navigation w/IDrive
Mods: M6 Wheels, Split Armrest, M-Steering Wheel, Euro Light Switch w/Rear Fog Lights, Short Shift Knob w/Matching E-Brake Handle, Clear Reflectors, CDV, Clear Bra

Retired:'04 X5 4.4i