Clunk, rattle, vibration when breaking



Since I've received my car I've had an issue when breaking at just about all speeds, but its more prevalent/noticeable when at lower speeds. If going 3mph (or any, its just nore noticeable at low speeds) I first hear and feel a clunking sound and then as I hold the break (when slowing down at higher speeds) it rattles and shakes/shudders as I slow down (makes a kind of knocking sound).
I at first thought it was something with rotors and in my head thought the first clunk was the pads grabbing rotors and then the rattle/shudder as it continually tries to hold a warped rotor or something, but I'm not so sure how and wanted to see what you all thought having more experience with other types of suspension issues out there on these cars. Its not exactly like the 'pulsing' sensation I get when I've driven other cars where only pads were replaced on an old rotor that probably needed turned/replaced.
Anyone run into this?
With the kind of sounds and vibrations you are discribing, chances are it's not just a warp rotor so it should be obvious to see what is wrong with the brakes.




Your front control arm ball joints have a pinch play in them. What that basically means is that the rubber bushing has worn to a point where the spindle in the ball joint is free to move up and down.
If you could see your wheel from outside while braking, you will see the entire wheel assembly bobbing up and down. Thats the clunking sound you hear as well.
Jack the car up with the steering wheel dead center, and hold the wheel at the 3 and 9 o clock positions and try moving back and forth. Then do the same at the 6 and 12 0 clock positions.
If you are able to move the wheel in both directions, youll have to replace the upper and lower front control arms.
It could also be cause by bent rotors, but then you wont hear any clunking and only the brake pedal will vibrate, not the entire car chassis.
Your front control arm ball joints have a pinch play in them. What that basically means is that the rubber bushing has worn to a point where the spindle in the ball joint is free to move up and down.
If you could see your wheel from outside while braking, you will see the entire wheel assembly bobbing up and down. Thats the clunking sound you hear as well.
Jack the car up with the steering wheel dead center, and hold the wheel at the 3 and 9 o clock positions and try moving back and forth. Then do the same at the 6 and 12 0 clock positions.
If you are able to move the wheel in both directions, youll have to replace the upper and lower front control arms.
It could also be cause by bent rotors, but then you wont hear any clunking and only the brake pedal will vibrate, not the entire car chassis.
Thanks for this info as i have changed my lower control arms and clunking reduced by about 90% but the upper ones are a PITA.Do you know the right sizes for removing the upper strut bolt and nut?Mine is an allen bolt.
Thanks in advance.




Did you happen to document the lower control arm replacement process? Would be great to have a DIY on here....even if you didnt document the lower control arms, make sure to take some good pics and do a writeup for the upper control arms when you get around to it.
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Did you happen to document the lower control arm replacement process? Would be great to have a DIY on here....even if you didnt document the lower control arms, make sure to take some good pics and do a writeup for the upper control arms when you get around to it.
Did not take pics on lower control arm replacement 'cos my wife lost my camera.But will do when i finally get to the upper as i had to buy a new camera yesterday.But lower control arms are easy but requires some muscle or power tools.I used some muscle.
Process is as follows:
1)secure rear wheels by E-brakes and chucks on both sides and jack up vehicle.Remove the (10) 8mm screws from splash guard under car then remove.Use jack stands to secure vehicle weight.There is a black rubber underneath frame in middle.Place jack stand there while still using jack.
2)remove front tire(left or right as i did both sides one at a time).
3)loosen LCA nut creating room to separate ball joint from knuckle.Don't remove yet to avoid injury.
4)use fork-like tool which i used by banging several times with hammer.I used this tool because the strut assembly stays intact.Will need to separate strut from wheel hub to remove upper control arm.
5)Loosen nut from bushing and remove taking note of bolt position for camber setting.Then finally remove nut from ball joint.
6)Install new LCA ball joint first and hold with nut.Install bushing part and turn the nut only so as not to damage the caster groove inside bushing.Do not torque yet.
7)Tighten ball joint nut.At this time you will need to hold the ball joint bolt with allen key to prevent joint from turning while you tighten the nut.
8)replace tire, remove jack and stand.
9)with car LCA under load, tighten nut only while holding bolt.Not sure of torque specs at this moment but this forum provides it under the (aftermarket & oem modification/DIY) if you google it.An alignment might be required afterwards.
Note:This procedure requires proper attention to detail and common sense to prevent severe injury and is at your own risk.
Last edited by pejaife; Apr 1, 2011 at 07:07 AM.
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