Zed82

Hi guys.

I have a problem with my 03 E500. I hear a clunk from the rear when i put some sudden pressure on the drive train from a full stop or from a very low speed. Itīs like a hard click. If i release the throttle right away after i hear the click as well.

Any ideas what this could be? I tried searching but no one seem to have had the same issue.

Zed82

140 views and not a single response? I know iīm new here but come oooon.

dsm2925

Are you sure its from the rear of the car?

Zed82

It sure sounds like it. I am not 100% sure though, these sounds can be deceiving...

dsm2925

maybe one of your rear calipers are sticking.

let see if some else comments-

Zed82

If it was the calipers, shouldnīt the sound be audible all the time?

The sound is only present when i put sudden tension on the drivetrain.

KEY08

"sudden tension on the drivetrain"- you mean when you gas it you hear the noise?
Brakes will clunk if the car has sat for awhile and got wet or cold/froze. If this happens every time you take off then you need to get it up on a lift.

PlatinumPi4u

check your tranny mount...

Zed82

Thatīs right. Every time i take off hard. If i take off slowly the sound is not there.

Update.

I drove the car yesterday with a mechanic sitting in the backseat. He sourced the noise to be coming from the rear left wheel area. Itīs only present on sudden jerks by pressing the gas pedal. Itīs not there when i tap the brake.

He will lift the car today and try to find the problem.

Any ideas?

Slivere63

My buddy had the same problem on his 03 E55. It was a worn rear sway-bar bushing. it took him 2 months and 4 techs to figure it out. Check that and see if it's a bushing. The other possibilities could be a Transmission mount or the internals of a catalytic converter have come lose.

BootieNH

My '05 E55 just started experiencing the EXACT same symptoms - loud clunk from stop when you hit the gas with any authority. Silent otherwise. And I get it when slowing suddenly also. My indie tech so far has also not had any luck finding it. Nor his Mercedes alignment specialist. The challenge is that it only happens under load, and he can't reproduce it when he lifts the car. I'll pass the sway bar bushing info along to him today.

edwinwalke

Have you taken a look underneath? Sounds like it could be a bad flexdisc on the driveshaft or possibly a bad CV Joint on an axle.

Without looking you are just going to be guessing. Put it on a lift and take a look.

BootieNH

My tech couldn't track it down, but did replace the sway bar links anyways, since they were relatively cheap. He "tightened everything down" real snug, and the problem disappeared. For about a month or so. Now it's starting to occur again. Trying hard to ignore it.

MPH 350SDL

I would suggest checking the flex disc as someone else mentioned, I would also have the mechanic check the subframe mounting bolts.

kkanuck

I have the same symptoms on a Mercedes Sprinter Van long wheel base with a NEW DRIVESHAFT installed by Daimler.

I will take all of these possible cures outlined in this thread to them to try and help them find the new problem....


Thanks and good luck, please update us with what happens...

BootieNH

Different tech, problem is back after about a month so maybe now more noticeable 'cause he claims to have it figured out... Anyway, subframe is the official diagnosis. Right rear, there are four bushings and it's the inside forward one(?), others sure to follow. Replacement of all four bushings on right rear is recommended. Was quoted $1500. Shopping around, going back to my original guy, who is trustworthy on cost...

crazypotato

I replaced my subframe mounts too. all four. I bought the parts from parts.com. labour was 6.5 hr. Unfortunately, the clunk noise is still there. Yesterday, I got mad. I took the spare tire out. Crawl under the right fuel tank area, drop the panel. starting to pad the gap between the strap and the tank like crazy with news paper. after it, I loosen the nut at the sway bar attaching to the weel carrier. It looked too tight. finally, i start to spray silicon lube at the sway bar bushings and all other bushings at the right wheel area. The clunk noise seems to be gone. WTF. I really dunno what fixed it.

Ichabod

When I take something apart in search of a reason for a problem, don't find anything, put it back together, and the problem seems to have disappeared -- followed by hours and hours of wondering what the heck I did, so that I'll know next time.

TheArchcardinal

I own a 320 and had similar clunk sound at the rear end of the car. I checked all arms, cambers and bushings and all were in perfect shape. I took a little time to observe the car's movement when I apply gas or let it stand on gear without holding the brakes. I discovered that the brake doesn't free up. I removed my brake pads to discover they'd been cooked up real good and the pistons in the rear calipers do not return.

I got steel pistons and filed down to size (since I couldn't get an exact match of the fiber type it originally comes with) and voila! All noise ceased and she purrs like a kitten. No more clunks or hesitation. I also have much improved gas mileage and more power. My advise, before fiddling with the suspension, the brake calipers are a smart place to start. Since changing them doesn't void you warranty and if you're out of warranty, you can give the steel pistons a try (at least they don't break and are smoother in sliding in and out). I live in Nigeria and. In spite of the heat, it works fine for me so far. I successfully did a similar experiment on my infinity QX 56 with 4 years under my belt. Its worth a try

hernangE320

I also have an 08 E320 (CDI/Bluetec), I just bought it and knew the engine mounts needed replacing (I suspect the previous owner liked to feel the 'push'). Both mounts replaced, runs much quieter/smoother now. But I have this 'thump' noise like there's a 5 Gallon jug full of water loose in the trunk. So any acceleration and I get the 'clunk', let off the gas and the same.
I have lifter the rear end and can get a fair amount of play/slop between wheels and driveline. Axles are tight as is driveline flexdisc. The 'play' in the differential IMO is the culprit..anyone else come up with why? I can't seem to find an exploded view of the differential. Anything helpful is appreciated.

JP500

I had this issue on my 03e500 and it turned out to be the bushings on both rear wheels. After I had them changed he sound was completely gone.

SuperChargerE55

Super happy saved me a lot of $$$$ Clonk noise solved

This is a good thread absolutely but I am sure what the most refer to here is
a hard clonk that only appears when from a complete standstill hit the gas quick little hard, or when rolling slowly like 5mhp doing the same, else it doesn't appear.

I say first inspect chassis bushings with the eye test all with a Pry Bar it will be visible if broken and is not that common as many say, seen it yes but not common AMG center told me this to and I saw the $$$$$$ raining down my face, then my tech inspected the rear Flex Disc yes it has some wear not much but he advised replacing it, found the Pelican Tech Article on Flex Disc replacement Super nice but be aware be sure have a large Pry Bar not like mine small skinny..
http://www.pelicanparts.com/techarti...ments_Bookmark

Did this today but pry bar to small and well Flex Disc looking really fine when taken apart so decided reinstall I just could not get pass Figure 7 was not able to push it so far toward trany to get clearance so reinstalled all creased it well inside before then tighten it accordingly
was down back to square one but test drive revealed Problem solved
No idea what problem has been but something with drive shaft rear or front no idea the clonk is 100% gone tested it hard acc from complete stop to accel I am so happy..

I will rapport back if it comes back surely. but please if is loud clonk very obvious mid rear is very loud really sounds really bad one bite the teeth hard II was sleeping bad lol $$$$ happy is solved

dannyfiveforty

Hi all,

I understand this is an old thread. However, I have a 2008 211 estate. Clunk noise only when abruptly letting the power off. No noise what putting power on.

A one time only thud from the rear when the accelerator is let off. I have had a bar in there and nothing is obvious. Mercedes Benz dealer looked it over and said it could potentially be the sub frame bushes or the flex disc. I have so far changed the disc which was very badly split, however, the noise is still there.

As a process of cheapest/easiest job by elimination what should I do next?:
a. Subframe bushes look to be ok with a bar in there and understand a very labour intensive job...
b. Change the diff bushes..
c. Change out the entire diff incase of play, But play I have been told is perfectly normal to have a rock back and forward (noticed when changing out the flex disc)
d. Anything else I could potentially try to isolate the noise? Or any potential cause I have ovelooked?
e. Exhaust isnt moving around and is not the cause.
f. My car is RHD and from driving seat the noises seems to be coming more so from the rear left. But, that could just be acoustics in the car and my seating position that is play tricks with me..

Many thanks
Dan

Plutoe

have you checked the drive shaft while on a lift as opposed to have your girlfriend listening in the back seat for the clunk

dannyfiveforty

Mercedes Benz dealer looked it over.