C43 (W202) Steering vibration & short lived front brake discs

[JamesM]

I am hoping that someone may be able to help diagnose a problem which is ruining my enjoyment of a great car. For the last 13 months my C43 estate has been suffering from two problems. Firstly a steering wheel vibration at around 63 - 70(ish!) mph and secondly it has required new front brake discs (with pads) every 3 - 4 months.
I have had the car for four years with no issues over the first three. It is a 1999 model with 67k miles on the clock.

The symptoms are that the vibration is always present around 65mph in normal driving. Over time it gets worse (2-3 months) being accompanied then by significant vibration & noise whilst braking from higher speeds (i.e. 50+ as opposed to around town). The car is then returned to an MB dealer who replaces the front discs under warranty and the cycle begins again.

The wheels (all 4) have been balanced (several times). I have even replaced one of the front wheels - just in case. A steering arm has also been replaced. MB parts always used. The tracking has been checked too. Rear discs have also been replaced.

Two MB dealers have checked every thing they can think of but can not suggest a cause. The first has now given up although the second is still on the case and is checking with MB HQ. (Although the first did this too.....who suggested it was my driving......Hmmmm).

Aside from not yet identifying the problem I can't fault the MB dealers for their service support and effort expended on this. Though I fear the end of the warranty support on the discs which has been mooted. Both agree that the problem is unlikely to be the discs (- unless MB have a faulty batch which I am working my way through!).

My presumption is that the steering wheel vibration is causing the brake discs to warp over time. This means that replacing the front discs cures the major symptom but not the root of the problem.

I would appreciate any suggestions of areas to look at so I can check with the MB dealers that they have reviewed it. I don't really want to part exchange my AMG for a sensible diesel yet but I am feeling compelled to do so.......please help!! Many thanks.

 

[Uncle Benz]

My feeling is you may have a problem with distortion on the front hub flange. The brake disc mounts to a circular flange which in turn is mounted on the front wheel bearing. If there is a distortion here, the wheel and disc will run out of true. It can be checked with a dial gauge for excessive run-out once the disc is removed.

 

[television]

I have little time today, but just to say that I have never in my life heard of brake disc causing a viabration when not braking and do not believe that they can.
I would go to a different tyre co to get the wheels balanced,there is nothing else,the wheels bearings even if loose would not cause it.

Malcolm

 

[Parrot of Doom]

I have exactly the same problem, although I haven't changed the discs recently.

The only thing I can think of is the bushes on the lower control arms are well worn, and that replacing them might eliminate this. A poster on a US forum recommended this, as it solved his problem.

 

[Bolide]

What happened 13 months ago? If the problem's been there since then, but wasn't before, something has changed

Are you the first owner? How long have you had it? Has it been smacked into a kerb? Was the car aligned / fitted with new wheels / lent to someone 13 months ago?

The only thing I've come across that is similar involved a bent hub, exactly as Uncle Benz said. If the car is vibrating when driving in a straight line then something is worn / loose / bent and swopping discs won't cure it

You might do well to do a chronological write up of all the work that's been done to the car then sit down with the service manager to discuss it. Clearly they haven't found the root of the problem. Fault-finding is an art and many technicians don't understand how to do it

Nick Froome
www.w124.co.uk

 

[Stevie A]

Jack up the front of the car and rotate the wheels on both sides. Then see if there is a rubbing / sticking as you rotate the wheel. Then you may be able to narrow down the side of the vehicle where the cause of the problem is.

I think it must be hub or suspension related and not the discs.

I had a distorted front wheel disc and it was "sticking on" when rotating the wheel.

 

[Dan996]

I dont think it is disk related i also have had warped disks on my old mitsi the only time i noticed was when i braked the pedal went up and down. Just for your reference if you do check it with dial gauge make sure you fix it to somthing solid that does not move and the disk should not exceed > 2 thou if it does you will feel it vibrate when braking only. I think like others have suggested it is a hub problem/wheel bearing. Good luck in finding problem

 

[JamesM]

I do agree that the problem is very unlikely to relate back to the discs. Each time they are replaced the issue goes back to the mild - but noticeable - vibration around 65mph. I.E. over time the discs are a symptom and not the cause.

I spoke to MB dealer two who confirmed that the front hub flanges have been checked and are within tolerances. It is the same 'ok' for the bushes on the lower control arms (and the wheel bearings).

After the initial wheel balancing didn't cure the problem they were all re done at another place. The latter has a very good reputation locally and took great care over it knowing the issue. Unfortunately this didn't solve the challenge.

For history I can recall nothing of note occurring to the car 13 months ago to suggest a cause. I don't 'molly coddle' it but I also don't drive it hard (as that wouldn't be easy on my traffic laden commute!). I'm the only driver (my wife prefers her Mini) and am overly cautious with kerbs so can't remember clonking one. I do recall the problem just starting with the growing wheel wobble and making noise under braking. This was diagnosed as the brake discs wearing out which were subsequently changed. And the cycle began. Each time the MB dealer said the problem was fixed but I could immediately point out the steering vibration.

By the way, the C43 wheels are its original AMG though they are all fairly corroded now.

Two different full sets of new wheels and tyres off demo vehicles have been put on the C43 for test drives to try and pin the issue down. The vibration was still there on these though was reduced a little. It was after this and another re-balance that I swapped out one of the front wheels with the spare (which was unused - & I did swap the tyres too) but no dramatic difference was noticed.

The car is now getting close to new tyre time so it may be worth looking at new alloys too. (Particularly given the unsightly wheel corrosion as I gather that refurbishment doesn't last more than six months). However, I am hesitant to start replacing parts without being able to quantify a wheel wobble benefit.

Re Stevie A's point, I can not notice any rubbing or sticking of either wheel which may suggest that the issue manifests only under load......which makes me wonder if it is really possible to accurately check the lower control arm bushes sitting in a garage.

One recent noise I have noticed is that at fullish lock there is a graunching sound when pulling away. Oddly, only coming out of my drive & at the tight junction at the bottom on my road. This is new. However, I saw another thread which suggested this could be related to low tyre tread, but FYI anyway.

As a speculative question; could there be 'repetitive strain injury' to the front suspension through driving over speed humps during the four years I have had the car? I suppose if there was damage from this then it would show up in the MB dealer checks........?

Thanks very much for the views & help so far.

James.

 

[Juddian]

Hi JamesM your experience has similarities to my own some years ago when i owned a Rover 827, which went like the clappers. Now then the brakes were absolutey fine but if your stopped hard from very high speed (which i'm not owning up to cos of vicars on this forum) a few times the discs would overheat and warp. Over my time with the car i must have fitted ten sets of fronts. Now you may not be driving that hard but it may be an idea to have a feel of the area close to the discs to see if you are generating excessive heat on your normal drive. Just a remote possibility that the calipers are binding? Brian

 

[Ultymate]

Has your steering damper ever been checked or replaced?

 

[Blobcat]

Quite rare now but if you could find a garage/tyre dealer who could balance the wheels on the car you may find the problem.

 

[JamesM]

Has your steering damper ever been checked or replaced?

Yes, it was replaced Feb 2006.

 

[JamesM]

Quite rare now but if you could find a garage/tyre dealer who could balance the wheels on the car you may find the problem.

I wish - I have previously looked but not had any luck near me (Sussex).

 

[JamesM]

Hi JamesM your experience has similarities to my own some years ago when i owned a Rover 827, which went like the clappers. Now then the brakes were absolutey fine but if your stopped hard from very high speed (which i'm not owning up to cos of vicars on this forum) a few times the discs would overheat and warp. Over my time with the car i must have fitted ten sets of fronts. Now you may not be driving that hard but it may be an idea to have a feel of the area close to the discs to see if you are generating excessive heat on your normal drive. Just a remote possibility that the calipers are binding? Brian

Hi Juddian, it's possible, but I didn't notice any excessive heat following 4 x 120 mile motorway journeys. Mind you I was collecting & returning Mother-in-law for the Christmas period so didn't do any aggressive braking.
My normal commute is around 25 miles of A roads in traffic which rarely beats 40 - 50 mph save for 2 miles of dual carriageway. I park in a well lit garage so would probably notice any glowing brake discs (I hope!). Though I'll specifically check when I return to the office next week.

By the way, after the last disc change in October I have been overly careful of the brakes just to prove (if only to myself) that I am not the last of the late brakers and killing the discs. They too are now juddering away merrily.

My commute hasn't changed which means the car completed three years of it quite happily before. (As did my BMW 328i coupe, Citroen BX 16v GTI & others before that).

 

[Blobcat]

I'm wondering if there is a problem with your calipers which is causing the problem with your brake discs. I don't know your setup but I know on bikes that it is quite easy for the calipers to stick.

 

[big x]

This reminds me of something older BMW's suffer from.The upper thrust control arm bush wear the first sign being vibration when braking then with increased bush wear vibration when the throttle is released because weight is being transferred forward and then finally a constant vibration at 50-60 MPH.At this point you can see the play just moving the arm with your bare hands however non-specialists will be convinced it's something to do with the brakes as the brakes and disks will also be wearing out quickly.In fact BMW vented disks are very resistant to warping.Both bushes tend to wear at the same rate.
Your W202 uses a much tougher double wishbone arrangement rather than an upper thrust arm but have the upper wishbone bushes been checked for play ?

adam

 

[JamesM]

Your W202 uses a much tougher double wishbone arrangement rather than an upper thrust arm but have the upper wishbone bushes been checked for play ?

adam

I don't know all the specific checks so far performed by MB but I will ask about this. Thanks.

 

[Parrot of Doom]

This thread may help, as I said, I'm having similar issues although they don't sound quite so bad as yours.

http://www.mercedesshop.com/shopforum/showthread.php?t=172894

 

[Parrot of Doom]

I found something else.

Click 'Tipps' from the left hand menu here

Then click 'W210 Lenkrad zittert'

You'll see some text and a picture. The rough translation is:

The steering wheel should tremble in speeds from about 60Km/h, the front Hydrolager of the lower breadth
handlebar are to be reviewed.

These are often leaky and lose the oil filling and therewith your function.

A repair sentence of Febi (included also the rear bushings of the breadth handlebar) costs about 30,- Euro per side. A new breadth handlebar out of the accessories from ca. 180,- Euro.

Which basically means that at speeds of about 60kph, the wheel vibrates, check the front lower control arm bushings. I'm sure you can figure out the rest

 

[GEORGEROV]

Bottom ball joints been checked?. Not easy to spot wear sometimes.