Thud sound coming from front suspension...
#1
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Thud sound coming from front suspension...
I have a thud like sound when going over bumps in the road. I thought it was my balljoints, which needed replacing and I have replaced. The sound has not changed at all. I have lifted the front wheels of th eground and put a crowbar underneath and bounced the crowbar to try to simulate the action of going over bumps to no avail and no looseness. Before I replaced my balljoints there was a slight wobble.
I was thinking that it might be the swaybar links at the end of the swaybar. I have purchased new inner swayabr bushings but not installed yet. The inner bushings don't look too bad so I don't feel they are the cause for the noise.
When I push down on the car from the passenger front of the car, I hear a squeak / creak from the passenger front. When I push on the passenger front up and down and hold the upper shock bolt that is exposed in the engine bay I can feel the squeak / creak.
The car in taking turns on the highway rides fine and hugs the road, just over bumps will you hear the thud coming from the front of the car..
Any thoughts?
I was thinking that it might be the swaybar links at the end of the swaybar. I have purchased new inner swayabr bushings but not installed yet. The inner bushings don't look too bad so I don't feel they are the cause for the noise.
When I push down on the car from the passenger front of the car, I hear a squeak / creak from the passenger front. When I push on the passenger front up and down and hold the upper shock bolt that is exposed in the engine bay I can feel the squeak / creak.
The car in taking turns on the highway rides fine and hugs the road, just over bumps will you hear the thud coming from the front of the car..
Any thoughts?
#3
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Originally Posted by RedVestEd
Replacing swaybar cured front end thud sound in my '01 W210.
#5
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S, GL, Escalade ESV, my shoes
Same problem happened to my car: a quite noticeable pop sound when going over bump. Quite anoying & embarrasing (when I have passenger along)
I changed to balljoints, as one of the mechanic recommend, and the problem didn't go away. Same as you, I had the car lift up and tried to simulate the wheel movement, but couldn't trace the problem. I spent a significant amount of time to debug the problem, w/ not much to help.
Suspension test (press on car) seem to indicate that shock was still okey. Called Phil at FastLane, he recommended a Bilstein shock HD (Heavy Duty). Took his recommendation, guess what ? NO MORE POPING NOISE OVER BUMP !!!
.
Turn out one of the front shock is softer than the other. Though both indicated as acceptable when doing shock test (press on hook and see how car bounce), this turn out causing the noise when car goes over bump.
The Bilstein HD worth every penny, oh, and it improve your car handling couple hundred percent !!
I changed to balljoints, as one of the mechanic recommend, and the problem didn't go away. Same as you, I had the car lift up and tried to simulate the wheel movement, but couldn't trace the problem. I spent a significant amount of time to debug the problem, w/ not much to help.
Suspension test (press on car) seem to indicate that shock was still okey. Called Phil at FastLane, he recommended a Bilstein shock HD (Heavy Duty). Took his recommendation, guess what ? NO MORE POPING NOISE OVER BUMP !!!
![Smilie](https://mbworld.org/forums/images/smilies/smile.gif)
![Smilie](https://mbworld.org/forums/images/smilies/smile.gif)
Turn out one of the front shock is softer than the other. Though both indicated as acceptable when doing shock test (press on hook and see how car bounce), this turn out causing the noise when car goes over bump.
The Bilstein HD worth every penny, oh, and it improve your car handling couple hundred percent !!
Originally Posted by michakaveli
I have a thud like sound when going over bumps in the road. I thought it was my balljoints, which needed replacing and I have replaced. The sound has not changed at all. I have lifted the front wheels of th eground and put a crowbar underneath and bounced the crowbar to try to simulate the action of going over bumps to no avail and no looseness. Before I replaced my balljoints there was a slight wobble.
I was thinking that it might be the swaybar links at the end of the swaybar. I have purchased new inner swayabr bushings but not installed yet. The inner bushings don't look too bad so I don't feel they are the cause for the noise.
When I push down on the car from the passenger front of the car, I hear a squeak / creak from the passenger front. When I push on the passenger front up and down and hold the upper shock bolt that is exposed in the engine bay I can feel the squeak / creak.
The car in taking turns on the highway rides fine and hugs the road, just over bumps will you hear the thud coming from the front of the car..
Any thoughts?
I was thinking that it might be the swaybar links at the end of the swaybar. I have purchased new inner swayabr bushings but not installed yet. The inner bushings don't look too bad so I don't feel they are the cause for the noise.
When I push down on the car from the passenger front of the car, I hear a squeak / creak from the passenger front. When I push on the passenger front up and down and hold the upper shock bolt that is exposed in the engine bay I can feel the squeak / creak.
The car in taking turns on the highway rides fine and hugs the road, just over bumps will you hear the thud coming from the front of the car..
Any thoughts?
Last edited by zam2000; 07-08-2004 at 12:48 PM.
#6
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I am planning on replacing all the shocks and springs in the future. I'm not in the finances right now to do it. I'm considering removing the swaybar and removing the inner bushings and outer swaybar links. Are these links available online, say at FastLane on mercedesshop.com.
What is the process to remove these swaybar links. I loosened one side on my swaybar a few weeks ago and didn't know how to safely remove it. I assume I have to totally remove the swaybar and knock them off?
Thanks Guys for the help thus far....
What is the process to remove these swaybar links. I loosened one side on my swaybar a few weeks ago and didn't know how to safely remove it. I assume I have to totally remove the swaybar and knock them off?
Thanks Guys for the help thus far....
#7
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Originally Posted by MARK CUMMINS
Inspect the Front sway bar Bushings / Links and The front lower control arm bushings..seen lots of them do this
Is it as simple as lifting up the car and unbolting the front screw that holds that bushing in place and re-installing the new bushing, then following the same procedure for the rear?
I just hope that I don't have to take the control arm out, thus removing the spring, etc....
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#8
I did mine on my 1997 E320 as there was a knocking noise almost while going over bumps. It went away completely after. To get them off, it was quite a bit of a pain. I finally ended up using a heat gun to get the rubber more workable. There probably is a better way, but this worked for me. You do not have to remove the lower control arm or anything else. The main thing to remember is to lift the whole front of the car up (both front wheels). If you only lift one side, the sway bar will have have a ton of tension when you loosen the bolt that holds it to the control arm. When you lift up both wheels, there is no tension in the bolt.
Steve
Steve