2008 GT. Been unable to be rid myself of a slight highway steering wheel shake for years. Doesn't really manifest itself until 50+ MPH, and it doesn't go away as speed climbs. IT IS ROAD DEPENDENT, i.e. glass-smooth roads produce virtually no shake in the steering wheel, while bumpy roads seem to make it considerably worse. At times, I have rationalized that it was nothing more than increased vibration from the lowered suspension and low profile tires but, in the end, I don't think its "normal." I have noticed no bump steer issues. Here's the changes as succinctly as possible. Most of the changes were not specifically to address the shimmy, but lots has been done: Purchased the car 2+ years ago. Stock suspension but 20" rims. Found one of the rims bent, so I replaced all rims (with new 20" Foose rims) and and installed new Nitto tires. Everything roadforce balanced then (and multiple times over the past two years), but the shimmy didn't change. About 18 months ago, installed Pedders adjustable coilovers to lower the car. At the same time, I installed camber bolts and a BMR adjustable front sway bar. Car aligned within specs. No change in the shimmy. A year ago, I decided to build up the motor. In the process, I found the A-arm bushings were bad, so I replaced both A-arms with the upgraded GT500 A-arms. I thought I might have stumbled upon the true shimmy problem, but it had no effect when replaced and car aligned. With the new motor installed, I put in a BMR lowered K-member, radiator support, cross brace, etc. Car aligned within specs. All tires roadforce balanced again. Still no change. So, as you can see, most of the front suspension, wheels, and tires, have been replaced over the years, with no real change to the shimmy. At this point, I'm down to the steering rack and tie rods, and those can be changed out for $300 in parts (plus alignment). But, I do have a car lift, and with the car up, I can get ZERO play in the rack or tie rods when I grab and tug on them, so it feels like replacing them would be a shot in the dark. I'm at a loss.