Clunking in front suspension on 2011 C300
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2011 C300
Clunking in front suspension on 2011 C300
Hi guys, I have a really bad clunking sound coming from the front suspension when on rough roads and dips. It sounds a lot like a loose top mount on a strut assembly when the top mounting nut is loose. I have zapped the top mounting nuts with an impact just to see if they were loose and they didn't budge.
I have changed the end links out with brand new Mercedes OEM units. I have also checked all control arm bushings, ball joints, sway bar bushings, etc and everything looks good. No leaks or cracks, etc.
The upper front control arm bushings don't show any cracks or signs of wear. They do have a tiny bit of play when twisting but I'm talking millimeters.
The only thing left that I can think of would be the strut assembly. Has anyone else had the same issue and it turned out to be the strut assembly? Any other thoughts?
Thanks!
I have changed the end links out with brand new Mercedes OEM units. I have also checked all control arm bushings, ball joints, sway bar bushings, etc and everything looks good. No leaks or cracks, etc.
The upper front control arm bushings don't show any cracks or signs of wear. They do have a tiny bit of play when twisting but I'm talking millimeters.
The only thing left that I can think of would be the strut assembly. Has anyone else had the same issue and it turned out to be the strut assembly? Any other thoughts?
Thanks!
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2011 C300
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Mercedes w204 4matic sport
Suspension noise is hard to trouble shoot. I had a light clunk going over bumps slow, tested everything and all checked out good. I don’t think ball joints go bad too often with this suspension design, and the bushings are fairly easy to test. My guess went for the cheapest part first-endlinks. Lucky me that was it. If you properly tested the ball joints and bushings the next thing I would do are the strut mounts as that is the next most likely source. The bearing in it could be bad. Next would be replace the strut imo.
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2011 C300
Suspension noise is hard to trouble shoot. I had a light clunk going over bumps slow, tested everything and all checked out good. I don’t think ball joints go bad too often with this suspension design, and the bushings are fairly easy to test. My guess went for the cheapest part first-endlinks. Lucky me that was it. If you properly tested the ball joints and bushings the next thing I would do are the strut mounts as that is the next most likely source. The bearing in it could be bad. Next would be replace the strut imo.
I had the same mindset in replacing the easiest and cheapest part first with the end links. Didn't help my cause but at least they are now new.
My next thought is the struts/mounts since all bushings and ball joints appear to be fine.
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Mercedes w204 4matic sport
Thanks, and I agree. Suspension noises are a pain in the *** to diagnose.
I had the same mindset in replacing the easiest and cheapest part first with the end links. Didn't help my cause but at least they are now new.
My next thought is the struts/mounts since all bushings and ball joints appear to be fine.
I had the same mindset in replacing the easiest and cheapest part first with the end links. Didn't help my cause but at least they are now new.
My next thought is the struts/mounts since all bushings and ball joints appear to be fine.
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2011 C300
Agreed. If you have a lot of miles though it might not be a bad idea to replace both at the same time since it’s the same amount of work. However, one thing I learned with my problem is the end links tested fine but they were causing the noise, so ball joints may seem fine but could be the problem though not as likely. Testing bushings is a lot easier to do. Depends on how bad it is.
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2011 C300
What I mean by upper is the top one of the two lowers haha. I saw some decent prices on Bilstein but I would need to buy the top mount and bearing separate. There are a couple companies that sell complete assemblies but I've never heard of the manufacturers. I think I might buy those just to see if the noise stops. Then once those go bad get some Bilsteins.
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Mercedes w204 4matic sport
What I mean by upper is the top one of the two lowers haha. I saw some decent prices on Bilstein but I would need to buy the top mount and bearing separate. There are a couple companies that sell complete assemblies but I've never heard of the manufacturers. I think I might buy those just to see if the noise stops. Then once those go bad get some Bilsteins.
Thats the arm that connects in the front correct? That’s the thrust arm, the one that goes straight in is the lower control arm. I would honestly say don’t bother with the unknown manufacturers for struts. They may be complete junk and not even fit quite right, they may even give you brand new mystery noises 🧐. I’d honestly get some Sachs or bilistein struts/OEM strut mounts and be confident they won’t be an issue. It’ll save u in the long run.
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2011 C300
Thats the arm that connects in the front correct? That’s the thrust arm, the one that goes straight in is the lower control arm. I would honestly say don’t bother with the unknown manufacturers for struts. They may be complete junk and not even fit quite right, they may even give you brand new mystery noises 🧐. I’d honestly get some Sachs or bilistein struts/OEM strut mounts and be confident they won’t be an issue. It’ll save u in the long run.
Yeah I would tend to agree. I honestly think the thrust arms are not the culprit. So maybe I'll take the money that would go to the thrust arms and put it into Bilstein struts and top mounts/bearings.
I have to remember this is only a daily driver, don't want to dump unnessesary money at it.
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From: SA
2008 C350-Sport-AMG-Active Agility Pack(Not reliable) +Izuzu KB6 3L(It seems Reliable)+Mazda
When I had my Mazda front shocks/struts replaced, I heard a clunking sounds only if I drive over a certain piece of road outside town, that was new to me.
Heard nothing pushing nose up or down, dealer also did this, refuse theres something wrong with the new ones.
In the garage this vehicle is parked, I had a piece of 30x30mm wood mounted on cement so the door closed to it. So a week later I accidently discovered if I reverse fast out of the garage I can duplicate the clunk. I brought the dealer home, illustrate it to him, and they replaced both front struts again, problem gone forever. I did contact the strut company and they offered free of charge replacement even if it was not the shocks. For what its worth.
Heard nothing pushing nose up or down, dealer also did this, refuse theres something wrong with the new ones.
In the garage this vehicle is parked, I had a piece of 30x30mm wood mounted on cement so the door closed to it. So a week later I accidently discovered if I reverse fast out of the garage I can duplicate the clunk. I brought the dealer home, illustrate it to him, and they replaced both front struts again, problem gone forever. I did contact the strut company and they offered free of charge replacement even if it was not the shocks. For what its worth.
Thread Starter
Junior Member
Joined: Jul 2019
Posts: 22
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2011 C300
When I had my Mazda front shocks/struts replaced, I heard a clunking sounds only if I drive over a certain piece of road outside town, that was new to me.
Heard nothing pushing nose up or down, dealer also did this, refuse theres something wrong with the new ones.
In the garage this vehicle is parked, I had a piece of 30x30mm wood mounted on cement so the door closed to it. So a week later I accidently discovered if I reverse fast out of the garage I can duplicate the clunk. I brought the dealer home, illustrate it to him, and they replaced both front struts again, problem gone forever. I did contact the strut company and they offered free of charge replacement even if it was not the shocks. For what its worth.
Heard nothing pushing nose up or down, dealer also did this, refuse theres something wrong with the new ones.
In the garage this vehicle is parked, I had a piece of 30x30mm wood mounted on cement so the door closed to it. So a week later I accidently discovered if I reverse fast out of the garage I can duplicate the clunk. I brought the dealer home, illustrate it to him, and they replaced both front struts again, problem gone forever. I did contact the strut company and they offered free of charge replacement even if it was not the shocks. For what its worth.
