I'd say take the wheels off and properly torque them all down -
This was happening to me and I believe it was partially my alignment which was cupping my tires and causing a shake, but I also think it was me not tightening the wheels down properly and using the wheel removal tools that the car gives you.
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2009 Brilliant Silver BASE 7AT | TEIN S-Tech Springs | K&N Drop Ins & z1 Maf Tubes | AAM S-Line Short Tails | 5% Tint | 20MM Spacers | Sport Spoiler NickTurnon's 370z Build
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