Author Topic: Thud feeling under sudden braking and steering wheel shimmy  (Read 3293 times)

achtungE30

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I'm hoping it is my CABs, as I did replace the CAs last year with my new suspension (bilsteins/h&r race), but not sure if the bushings were included with this.

It was very apparent last night when I had to do a close encounter panic stop and I felt a hard thud below. After releasing the brake I hear/feel something shift underneath. I tried to see if I could move my wheel with the car jacked up but couldn't reproduce it so maybe it only happens when the front end weight shifts. Oh and my car begins to vibrate and steering wheel shimmys like crazy at above 85mph indicated.

I have a set of treehouse CABs arriving today and will probably go on at my earliest convenience.

What do you guys think.

- 91 318is (loves to warm-start-stall
- 08 135i European Delivery 9/18/08

b318isp

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Thud feeling under sudden braking and steering wheel shimmy
« Reply #1 on: July 26, 2007, 11:15:54 AM »
Sounds like a place to start. Could the noise have come from the rear? May be subframe mounts, but given the vibrations, you're probably right..

dude8383

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Thud feeling under sudden braking and steering wheel shimmy
« Reply #2 on: July 26, 2007, 12:16:29 PM »
tie-rods, control arms, more specifically your ball joints?

the lolli-pops are a good place to start as well.

jack up the car, and see if the wheel has any play on hub too, as well play in the ball joints.


achtungE30

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Thud feeling under sudden braking and steering wheel shimmy
« Reply #3 on: July 26, 2007, 02:20:01 PM »
Quote from: b318isp;30462
Sounds like a place to start. Could the noise have come from the rear? May be subframe mounts, but given the vibrations, you're probably right..

Def. coming from up front, the thud can be felt in the steering wheel as well as being audible...at higher speeds, heavy braking can cause the steering to fight me into a direction also. At first, i was thinking it was the new brakes, maybe the caliper or rotors are a tad loose as I just did them, or the pads may not be seated properly in the calipers as my HAWK HPS pads didnt come with anti-rattle clips nor any clips that hold them onto the piston, they just sit there.

- 91 318is (loves to warm-start-stall
- 08 135i European Delivery 9/18/08

BrandC

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Thud feeling under sudden braking and steering wheel shimmy
« Reply #4 on: July 26, 2007, 05:55:10 PM »
Make sure your rotors are not warped and properly installed. If the shaking only happens when you brake, make sure your caliper bushings are not ripped and your rotors are bolted in. I had that problem on an E36 and we changed the rotors, problem solved.

As far as the thudding goes, make sure your strut mounts are in decent shape. Also check the balljoints and tie-rods, very common failure item on many generations of BMW's. The thudding is most likely a product of worn out suspension items that now have a lot of slack.