2MCHCAR

I want to add to the W209 troubleshooting knowledge base. Ever since I installed my H&R sway bars, I've had a "Clunk" coming from the rear passenger side area, here is a diagram of the rear sway bar area:

I've replaced my rear shock and torsion arm (70), with no luck. Today I found the culprit, the screws holding the sway bar bushing (60)! I checked both sides and both had loose screws. I tighten them down, then checked my CLK shop manual DVD for torquing values; I found out they are single use only and need to be replaced (I'll do that later). I took a test drive and it solved the problem!

dynomite05

Congrats, I'm sure you arent the only one with this problem.

Jamesbbh

Could you just Loctite them?

2MCHCAR

LoL! I guess you could, but since I'm always buying things from Parts.com; it buying some new ones shouldn't be too much trouble.

betrezra

That SOUNDS like my problem. Time to do what MB forgot.... tighten my nuts.

Nando87

+1 , that sound has been annoying me for a long time

mikata

LOL, in an other meaning

betrezra

....

lowpost

That was my problem on the front H&R bars - I posted back in the Spring. My shop didn't mess around and tapped new threads for larger BMW bolts.

2MCHCAR

Update:
My rear sway bar was modified and thickened to compensate for the new exhaust and my rear sway bar rod bushing failed. I followed the advise from the thread below and it fixed the problem.
https://mbworld.org/forums/c32-amg-c55-amg-w203/198608-found-another-failure-point.html

Flame3g

Are the front sway one time use only as well. I here a cluck sound when i reverse then shift to drive then hit the brakes. Thought it might be my pads against the rotor

2MCHCAR

Are you sure the clunk is coming from the front? It's more rare, but it is possible. Take a look at the tread below; it's for W203's but the suspension is about the same as your W209.
https://mbworld.org/forums/c-class-w...placement.html

Flame3g

I think so, one of the link were replace by the dealer and the sound toned down alot but came back. When I had my sway bars put in i did not use new hardware only new bushings for the front. I will look at the links.

bheng

is it easy to get to the end links with just a lift?

I am considering this a possibility. I am getting a clunk when i hit uneven road sometimes. took the wheel off to see for any loose parts and nothing. so i think it could be sway related...

Flame3g

I replaced the front bolts and the sway bar end links and torqued them down still a noise when i go into reverse and press the brakes and when i put it in drive and press the brakes. I will replace the rear sway bar bolts, torque down and report back.

chanyboi

Were you 'clonkings' over speed bumps? When i go slowly over speed bumps my car sqeeks, when i go over a little quicker there is a slight clonk from the rear.

If so, does anyone know the part number for new bolts/ bolt size and thread pattern?

sirswift93

Did you ever figure out where the clunk was coming from? Sounds like the flex disks on your drive shaft are in bad shape. When they dry out they flex too easily and allow the propeller shaft move too abruptly; causing that sound.

TechSuperstar

I'm getting the same clunking noise from the rear. I bought the links and bushings but I'm afraid I might have the wrong bushings. I got part #2033260181 rear bushings but my car has the appearance package and the dealer said it needs part #2033260081. I peeked under the car quickly and it looks the same. Does anyone happen to know if these are interchangeable? Does the appearance package have a thicker sway bar or something? Thanks.

DRACO

Check the front wheel well plastic mud guards.

My passenger side linkage broke due to a fail strut and went past it's designed point and bent the guard causing to make a plastic clunk sound over speed bumps.

Inspecting it, I found the linkage bolt was also rubbing against it.

Used a heat gun to put back into shape and replaced linkage on both sides. New struts completed the process. Smooth as silk and no more CLUNKS.

DanielFD

Btw guys there is a TIPS document that is in the w209 wiki on mbworld (for some reason it seems to be down now, so couldn't past a like) about the rear screws that attach the shocks to the bottom of the car. There is an updated number for the screws and nut and the symptoms were clunking noise over bumps in the rear suspension. Personally i changed those screws and nuts out but i also changed our the rear shocks because they were shot anyway, and my clunking noise went away. But I really dont know if the screws solved the issue or if it was just the shocks that were shot.

KDD896

having the same problem myself will see if this fixes mine

Eojj

I think i have this exact same issue. Will give this a try before I overhaul the entire suspension. Does anyone happen to have the part # for this screw holding the brackets/bushings?