pjrbsl

Hello to all.

I am new to the forum and this is my first post.

I recently purchased my first Mercedes. It is a 2015 C200 sedan with about 27,000 km on the clock.
During the test drive it ran very quietly and smoothly.
The dealer had it serviced prior to handing it over to me.
While I was driving home a humming noise started to come out of the front left hand side of the car when driving around a right hand bend in the road.
And the noise didn't happen when driving around a left hand bend or straight ahead.
I have also noticed that the noise starts as soon as there is the slightest movement of the steering wheel to the right.
I thought it was a wheel bearing or suspension or steering noise so I took it back to the dealer and they sent it to a Mercedes workshop for investigation.
They say they have completely disassembled the LHS wheel, bearing, etc and have found nothing that could cause the noise.
Their latest explanation is that "This is a known phenomenon in this model of Mercedes car”.



Does anyone else have this type of issue?

Has anyone heard of this “known phenomenon”



I am currently thinking that if it is not bearing, steering, or suspension related that maybe it could be tyre noise.

I have Continental tyres: 225/40R19 Front and 255/35R19 rear.

What else could it be?

JAMADOR

Mine went into the shop this morning for the same thing. LF sound, like a wheel bearing. Louder during right hand turns, none during left turns.

pjrbsl

Jamador,

I would appreciate any feed back you can give about how the issue was resolved.

JAMADOR

Heard from the dealer today.
They said they inspected the bearings, no issue. Noise likely from cupping on front tires. They 'made some adjustments' so we'll see how it is when I pick it up tonight.

I picked up my C in late July, CPO, so it had new tires on it. I think I have about 8k miles on it since then. Definitely not putting another set of these Continentals on when it's due for new tires. Probably go with Michelin Pilot Sport A/S 3+ like we have on our Flex. Have driven them in multiple weather conditions with no issues.

pjrbsl

Thanks heaps.

I'm pulling my hair out over this issue...they have had my car for 5 weeks!!!

I have new Continental run flats on my C200 so it may be the same issue.

I think I'll ring them and ask the obvious question: "Have you checked the tyres?"

Be very interested to know if your car noise disappears or reduces...

pjrbsl

I just remembered that when we got home after we heard the tyre noise there was rubber tyre dust in the wheel arch and on the side of the car.

But as the tyres were newly fitted before we purchased the car, and on inspection they looked like new, we assumed they were just "wearing in" didn't associate the dust with the noise.

I'll scream if they tell me that is the problem!!!

JAMADOR

The reviews on the Coni run-flats are definitely not glowing. A lot of complaints about short treadlife (10-15k miles).
for a set of tires that runs $1,200USD installed, I'll gladly switch to a higher treadwear rating, on a tire that I'm familiar with, even if the tradeoff is a slight loss of max performance.

pjrbsl

Well it seems that the issue is the steering rack.

The dealer is now arranging for the steering rack to be changed.

As most cars do around 20,000-25,000 km per year and Mercedes have a 3 year new car warranty you would think that they have designed their equipment to last at least 75,000 km.

So as my car has only done 28,000 km I can only assume that the previous owner/driver has had an incident where the left hand front wheel has hit something pretty hard.

I am hoping to pick my car up sometime this week to confirm that the noise had gone.

pjrbsl

Well the noise has gone and the steering is much more direct than before.

shang12

it could be your front axels I just had that issue with my c400 and when I would make a slight right or left turn at low speeds like 20-30km/h I would hear a ticking noise and it go away, and I didn't always hear it and I took it in and MB said its the axels and will replace it.

hope that helps

pjrbsl

Shang12,

Thanks for the feedback!!

After a couple of weeks of trouble free driving with the new steering rack I am convinced that the previous owner has driven the left front wheel and hit something (probably a roadside kerb) and that has damaged the steering rack.
The reason for me believing that is that the dealer tried to get it reconditioned by a repairer but after disassembly of the old unit it was not repairable and so they replaced it completely.
Hopefully now we will have no more issues with this car.

JAMADOR

Glad that resolved it for you.
My switch to new tires rid my car of the wheel bearing sound (cupping on LF tire). So much quieter now.

shang12

Mercedes makes very **** quality cars now days...I found that out too

traveller78

Hi, how did your dealer determine it was the steering rack problem? I have a rotating sound from the front right. Situation is similar to yours.

Andy74

I have to say that my C200 was on run flat tyres and it was quite noisy, i got rid of these run flats and switched to Yokohama Advan Sport V105s. The ride is much more quieter mainly from the front. As you know there is no room of any sparewheel in the trunk wether a spacesaver or not... I already have a subwoofer in the trunk, i purchased a 19" spare wheel as i was not able to find a spacesaver also the dealer had to order it and its expensive. So now i am looking for a cover bag for my sparewheel.

Simon Guertin

I have purchased the spare wheel from the E-Series, much cheaper. It clears the sports brakes. They also sell a nice mercedes spare wheel bag that attaches to the trunk's 4 corner hooks.

Andy74

Can i ask how much did you pay. I assume it was not a space saver.

traveller78

I had suspected it was the front right tyre. So i swap left to right. The sound remained. I've upgraded from 18 to 19" and new PS4S. The same rotating sound remained when I veer left at speeds above 80kmh. The rotating sound's frequency is constant, it doesn't get louder with high speeds non, softer and lower speeds. In fact there is no sound below 60kmh, which I find weird.

What are the symptoms and effects of a defective steering rack? Does anyone know?

Andy74

I found this for you:

https://www.autoblog.com/2019/08/20/...g-rack-gearbox/

C200 2015

Recently bought C200 2015, it looks so good, but there are couple of things that is concerning me right now.
1. There is a lot of road noise in the cabin. I have continentals currently, 225/40/r19 Y XL in the front & 255/35/r19 Y at the rear.
2. Brake grinding sound at crawling speed to a stop, checked with the mechanic but there seems no issue with the pads nor the discs.

MaverickC43

Run flat tires?
they are loud

C200 2015

So which tyre would you suggest? To avoid this road noise. (19inch)

MaverickC43

I didn’t read through this whole thread.
Not sure what noises ur hearing
Ive had conti dws06+ AS
and mich ps4s summers
Either one, really any non RF, will help with road noise. But clearly other noises will not be helped by this