I Am Jacks Merc

Hello all,
Haven't been able to find a match for my particular situation in the forums. I have an '08 S550 4MATIC, 180,000kms.
There's a strange vibration / buzzing noise coming from the front of the car that's especially noticeable when I drive slow, seems to be from the left side. Vibration can be felt in the steering wheel.
Doesn't matter the position of the steering wheel and it only happens when the car is moving (forward or reverse). As soon as I stop, it stops. Car can be cold or warm.
It's there when braking, or if the car is coasting in neutral. Sometimes there's a weird click and then it stops for a few seconds.
I've taken off both front wheels to see if there's something dragging on the wheels & brakes but everything looks fine. Pads were replaced in the last year. CV boots are all in good shape.
I thought maybe steering related, but there's no noise when rotating the steering wheel when stopped (I topped up power steering fluid anyway, no dice). Steering wheel feels normal, doesn't pull.
Wheel bearings? But then why would it sound fine 20% of the time?
Scratching my head. Any thoughts?

JohnLane

Where does the ABS pump live?

Engine mounts do screwy things when they are bad.

Going to have to do some more sleuthing.

I Am Jacks Merc

I looked into both those you mentioned. I don't think it's abs, the brake feel hasn't changed and it's happening even when the brakes aren't applied, no warning lights also. Engine mounts - issue doesn't occur when the car is in park or when reved.
As you said, more sleuthing...

BOTUS

which suspension system does it have ABC option or the std airtragic

if you have ABC sounds more like some of its usual fun to me

I Am Jacks Merc

It's the air suspension. Sound occurs at standard height or raised.

vettebk

How many miles on the car and have the engine mounts ever been changed. Engine mounts on a Mercedes are considered maintenance items.

You can test by putting the car in drive with the hood open, holding the brakes hard, and accelerating. If the engine lifts while doing this, you know it is an engine mount. There is oil inside the engine mount and as the oil leaks down, the engine touches the frame and makes a vibration. Fix the engine mounts and your vibration will disappear. Ask me how I know.

Good luck.

I Am Jacks Merc

Took it the mechanic today, couldn't get the noise to come back...right until I got home. Didn't do it during about 25 minutes of driving. Ugh.
If it were the engine mounts, it would be a constant noise, no?

vettebk

Typically as you accelerate with a bad engine mount, the engine touches the frame and you get the noise/vibration. Do the test I quoted and report back. You will know right away. Not hard to do.

tbilisi79

I went through all this.
get MB mounts. MB trans mount. Clean TB. And pray to god it gets better. And it still won’t be Lexus smooth.

I Am Jacks Merc

Update:

The second time I tried to take it to the mechanic, it again stopped making the noise, and I haven't been able to get it to make the noise since.
They figured it could be a vacuum pump, but if so, it should get worse, not go away.
All I can do is guess what it was, my money is on something with the ABS making it rapid fire engage / disengage.
I have a video of it making the noise, but can't find a way to upload it.
Anyway, thank you everyone for your suggestions and help.

vettebk

Ask your technician to check your engine mounts. Mercedes uses an oil filled mount and over time they leak down reducing the clearances between the engine and the frame. Mercedes considers it a maintenance item. An American car can go 25 years with no motor mount issues but a Mercedes will go through three sets of engine mounts in that time.

The Thomas J

The upgraded mounts are supposed to be better.

BenzV12

You sound like my dad

vettebk

Yup! I will be 73 years old this year. So I probably think just like your Dad.

BenzV12

He's 75 years old and he always praises how solidly built those 50's -60's Americans namely GM cars were .
Even a 4 banger Mercedes-Benz engines require those replacements after a while but I don't take it as a negative point to the Mercedes-Benz brand

vettebk

Your Dad sounds like a great man!! I agree with him. 50s/60s GM, Mopar were all such solidly made cars. I still love my Mercedes S600 but often wonder about the over-engineering and massive maintenance requirements. I don't ever recall a GM spark plug costing $10 each! My S600 eats 24 of them at each tune-up! Thank heavens I can afford it.

Please give your Dad my best regards.

WRC-LVR

Yikes 24 of them at even $10 each is $240 plus labour.... What is the going MB rate for the plugs? RockAuto has the iridium Bosch plugs with preset gap (,028 ) for $6.88 each for your 2007 S600 TT.. Most likely the OEM are Bosch too...Iridium last longer too

vettebk

https://www.fcpeuro.com/products/mer...0-ngkttplugkit

vettebk

and here is the OEM!!!!

https://www.mbpartscenter.com/oem-pa...EyLWdhcw%3D%3D

BenzV12

Thanks , I will do it with a great pleasure

I'm glad you can afford the maintenance cost of your car . Especially S65 AMG requires even more .

WRC-LVR

Geezus OEM MB $14 each x24 $336 for plugs ??? Note to self never buy a v12 dual plug engined MB....

vettebk

I really do love my S600. When my V12 is under full boost and accelerating like a jet, I lose track of the cost of those spark plugs.

JohnLane

Try one that is healthy and happy. Many things we spend money on as it is worth it.

One need not purchase plugs from MB.

vettebk

Absolutely true. I am actually old enough to remember buying a spark plug for 59 cents at Pep Boys. It wasn't iridium but it certainly fired my Mopar. Does Pep Boys even exist anymore?

WRC-LVR

yes it does in Georgia anyways