Rear suspension noise Clunks on bumps while driving?

2014 MERCEDES BENZ CLS550
117,000 MILES • TURBO • AUTOMATIC
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BHAMDOC1
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Clunks on bunps while driving. While parked and pushing on the trunk side i hear it from driver side. It looks like it has strutmaster strut. Does this sound to you like a strut issue?
Jul 4, 2026 at 11:50 PM
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BHAMDOC1
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I believe these usually have air suspension and most owners replace them with strut master kits. This one I see has a strut master rear strut and the air pillow was replaced with a spring. I say that because there is a disconnected wire that usually goes to the pillow, which is not there anymore. Can you find m=out how I can get to the top mounting bracket on top of the spring? the bolt and washer maybe loose
Jul 5, 2026 at 12:15 AM
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STRAILER
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This can be anything on the suspension, I would check the sway bar links as well but if everything thing looks okay chances are the struts are bad. I have marked the diagram below so you can check it out. Check out the images (below). Let me know how it goes
Jul 5, 2026 at 2:54 PM
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BHAMDOC1
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Could not really find anything loose or even close. Had it all in the air. Only thing i see is that struts have some
Residue, not sure if that can mean that they were leaking before. Can you find out for me how do i get to the top bolt of this struts which is not an air struts? Its a conversion lit and i have a suspicion the top nut/washer or top mount bracket is loose or seteriorayed
Jul 10, 2026 at 6:04 PM
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BHAMDOC1
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Attached
Jul 10, 2026 at 6:24 PM
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STRAILER
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O ya, that sock does not look good, when they leak like that they are coming apart internally which can make the noise. Here is the diagram to help you remove it so you can install another.
Jul 10, 2026 at 8:25 PM
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BHAMDOC1
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I cannot find where the 2 bolts on top are located. Can you see if the rear seats need to be remived and how to remove the top cover under the rear windshield
Jul 10, 2026 at 11:09 PM
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BHAMDOC1
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here
Jul 11, 2026 at 12:57 AM
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STRAILER
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Yep, that shock is bad for sure, you can see it. Yes you need to access the upper bolts through the trunk or rear seat. Thanks for the video, let me know how it goes.
Jul 11, 2026 at 2:49 PM
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BHAMDOC1
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I found it deep behind the cargo covers. Removed it abd explained it in the video. If i to replace it i have ti fet an afternarket shock if i can find it, because stryt masters doesnt sell individual parts except to original owners with proof of purchase. Only thing i found was the originals which has a harness connector on each side of the rear. Do you know if these act as regular shocks? Not sure if they have to be plugged in because if an not mistaken when the strut conversion happened an sure they installed the cluster warning light module which eliminates these lights, which comes with the kit. Rear has regular coils. The last picture is i believe the original ones. If it is going to act like a normal shock i will get it. But if the connector must be plugged for it to function then i will be maybe creating more issues than i need
Jul 11, 2026 at 3:06 PM
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STRAILER
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Yep, thanks for videos, these shocks must have a plug in for the light to go off or you needs the adapter to turn the lights off, they have different dampening rates depending on mode and driving conditions. Nice work finding the access to the top of the shocks.
Jul 12, 2026 at 4:59 PM
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BHAMDOC1
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Thanks. What am saying is that this car must have had the light off module that cancels any messages on the dashboard. It has no lights on the dash as strut masters usually sell the kit with the module. I say this because the plugs that connect to the original struts, same as the black ones in the last picture, are still there but just hanging/disconnected. So now for me to replace the strut master shock absorbers, and since I cannot buy a replacement from them since they don't sell individual parts, I have to go with the black ones with the plugs. But what am asking will these serve just like the regular shock absorbers if I install them without connecting them?
Jul 12, 2026 at 6:59 PM
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STRAILER
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Yes, they should have a default setting that will act like a regular shock.
Jul 13, 2026 at 2:36 PM
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BHAMDOC1
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Found a single absorber for the car in china, installed and no more clunking. Really strange that you cannot buy a single one here in the US while strut masters wants you to spend $1900 to buy a full kit instead of selling you one. $120 fix and all is good
Jul 21, 2026 at 12:19 AM
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STRAILER
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Glad you could get it fixed, thanks for letting us know.
Jul 21, 2026 at 3:33 PM
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