E Class Suspension Knock

[brian atkinson]

I am the owner of a 53 reg E320 cdi and have had a rumbling/knocking noise that appears to come from the inside front suspension. The problem first occurred in the first year of ownership and despite the car spending days in the Nottingham Mercedes dealer and eventually having both front shock absorbers replaced after the warranty ended the problem persists and they have asked to have the car for yet another day at my expense to check the joints, struts etc. The problem is particularly bad on gravel and rutted surfaces when it sounds like a woodpecker. I am not convinced that Mercedes have any more idea than myself as to what the problem is. Has anybody else had this problem and can they suggest what it may be?

 

[Aussie Nick]

I think member Brandonwood-Dixon may be able to assist you when he sees the post. There is a DIY post by him recently on replacing the lower ball joint which you might pick up if you trace back through his recent posts

 

[karlefr]

I have the same problem on a W210 200K 2001, I got it checked twice (two different dealers), no result, everything is sound, except the sound! Very annoying, so!

 

[Kevin Gardiner]

Sounds like the front lower suspension arm bushes to me. I have changed quite a few of these in the last few months.

 

[karlefr]

Sounds like the front lower suspension arm bushes to me. I have changed quite a few of these in the last few months.

hi, I'll get it checked out next week!, Thank you,

 

[brandwooddixon]

I must admit I'm not impressed by the service that you've had so far.

Knocking noises on the front usually occur due to worn lower ball joints or anti roll bar drop links. Due to the nature of the suspension ball joint play can only be assessed whilst weight is applied to the lower wishbone.

MB use a sizing guage to check for ball joint "stretch" - this is caused by wear and the tension applied to it by the main spring.

For a W211 the lower ball joint is a push fit into the lower wishbone, get this checked for play.

I have heard of rumbling caused by worn wishbone to chassis bushes, but that is not very common.

Similarly I have come across worn steering dampers causing a knocking noise, but I'mnot sure if that applies to your vehicle.

 

[Aussie Nick]

Sorry Chris I mispelt your forum name in the earlier post. It was late and I was tired . Apologies

 

[brandwooddixon]

No problem