clunking suspension noise at rear
#1
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at about 30 plus mph on rough or bumpy roads there is a clunking sound. like metal to metal but not high pitch. here are observations on the suspension visible parts.
the car shop i go to do not think it is from the sway bar parts. the opinion is something loose inside the shock.
- air shocks appears ok externally and is working. nothing loose at mounting points.
- the sway bar bushings have partly moved out to the right side.
- the sway bar links bushings ok.
- impact marks between sway bar and wheel inboard edge.
- could it be something loose inside the air shocks?
- can this make a clunking sound. no looseness between rubber and metals.
- the rubber semi deteriorated and so compressed beyond design limits thus metal to metal contact. i checked this angle. nope. rubbers are ok.
- possible that the sway bar is sliding axially to left and right when car is running on rough roads. that at this time the bushing allows this motion.
the car shop i go to do not think it is from the sway bar parts. the opinion is something loose inside the shock.
#2
Senior Member
at about 30 plus mph on rough or bumpy roads there is a clunking sound. like metal to metal but not high pitch. here are observations on the suspension visible parts.
the car shop i go to do not think it is from the sway bar parts. the opinion is something loose inside the shock.
- air shocks appears ok externally and is working. nothing loose at mounting points.
- the sway bar bushings have partly moved out to the right side.
- the sway bar links bushings ok.
- impact marks between sway bar and wheel inboard edge.
- could it be something loose inside the air shocks?
- can this make a clunking sound. no looseness between rubber and metals.
- the rubber semi deteriorated and so compressed beyond design limits thus metal to metal contact. i checked this angle. nope. rubbers are ok.
- possible that the sway bar is sliding axially to left and right when car is running on rough roads. that at this time the bushing allows this motion.
the car shop i go to do not think it is from the sway bar parts. the opinion is something loose inside the shock.
#3
clunking suspension noise at rear
Yes I have seen this video before. And yes my sway bar is in this condition. So based on being in similar situation, the solution should be the same. However, it has not reached any witness mark of parts conflicts as in the video. And my mechanic so far do not think this situation can make the clunking noise.
Mercedes issued a TSB to glue the bushings. I have to check details. there is a chat about this subject in You Tube. This implies that there is a factory tool to push back rubber sway bar cushions.
I am designing a fixture to restore the bushing position and glue it. The cost of dropping the rear end sub-frame just to replace the sway bar assy is very expensive (quoted labor time is 8 hours). I just paid $1000 for fixing the radiator leak which i consider a design defect. And before this more major repair costs never seen happen on other cars.
replace fuel tank to fix fuel gage issue.
replace rear crank seal
replace head light washer pump.
replace low beam head light bulbs.
replace vvt cover on front of cylinder heads
replace radiator.
replace front sway bar assy.
replace front shock's sensor switch
replace engine mounts and trans mount.
Thank you for your info.
Thanks for the reply.
added more too soon maintenance done:
factory brake pads and rotors new set made only 16k miles. replaced with after market ceramics now working great.
Michellin Sports tires do not last more than 10k-12k miles. I used two sets of tires so quickly. I changed to Continental DWS 06 X LOAD (103). Happy with it.
Mercedes issued a TSB to glue the bushings. I have to check details. there is a chat about this subject in You Tube. This implies that there is a factory tool to push back rubber sway bar cushions.
I am designing a fixture to restore the bushing position and glue it. The cost of dropping the rear end sub-frame just to replace the sway bar assy is very expensive (quoted labor time is 8 hours). I just paid $1000 for fixing the radiator leak which i consider a design defect. And before this more major repair costs never seen happen on other cars.
replace fuel tank to fix fuel gage issue.
replace rear crank seal
replace head light washer pump.
replace low beam head light bulbs.
replace vvt cover on front of cylinder heads
replace radiator.
replace front sway bar assy.
replace front shock's sensor switch
replace engine mounts and trans mount.
Thank you for your info.
Thanks for the reply.
added more too soon maintenance done:
factory brake pads and rotors new set made only 16k miles. replaced with after market ceramics now working great.
Michellin Sports tires do not last more than 10k-12k miles. I used two sets of tires so quickly. I changed to Continental DWS 06 X LOAD (103). Happy with it.
Last edited by Honorio Lim; 07-04-2019 at 05:37 AM. Reason: more info added