Originally Posted by wc123wc
Ok, so I had the thrust arms replaced at RMP Motors and the car feels so much better now. The front wheels and steering wheel feel much tighter. The front end doesn't tremble when I hit an uneven surface any more (such as when entering a parking lot). The shimmy has been greatly reduced but it's still there, and I feel it especially between 120-125km/h. I feel this shimmy mainly in the gas pedal, floor of the car, and seats a bit.
PS: My car is really a great drive but I am one of those people who pick on every little thing. Every one who test drives it tells me that it's a great drive and better than anything they've driven. But I am not satisfied with that--I want that shimmy problem solved or at least identified.
I have the same issue... VERY minor shimmy at exactly that same speed... (120) - goes away above that speed and below that speed. RMP is quite familiar with my car as they have helped me maintain it to pristine shape for years (350K now). I apologize but I do not recall what Rocco's hypothesis is for that tiny shake in my car at that speed but he did do a thorough inspection on it and drove it the last time I was there last week. In my case it is a very minor tremble at exactly that speed and I too am very nitpicky about the driving dynamics of my car but chose to hold on this for now and monitor to see if it gets worse.
I will mention it to him again and let you know if he recalls what it was on my car - maybe it will help you out too.
Is your steering wheel vibration during braking resolved now? If not I can tell you from my experience that I had the same issue as well and the root cause was warped front rotors. I drive about 50K a year (mostly hwy so not a lot of braking at all) and I had my brakes done at BMW about 21 months ago so they replaced my rotors and pads under warranty - that solved this problem entirely.
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