Hello all,

After a long 17 yrs with E32, E38, and E39 BMW's, I've finally decided to come over to your side and start a new journey with a W221.. I purchased a W221 S350L, with 103,000KM, single owner car, and have driven it about 2000KM in the month I've had it. So far, I have a couple of questions, I've searched & read every single thread related to these issues, but it's always best to ask when in doubt..

a) Vibration between 100-140KM/hr, comes through the floor and it feels as though the entire car is vibrating. It's strange that if I run the car at 95KM/hr, there is zero vibration, it starts at exactly 100KM/hr. There is a tiny amount of steering wheel vibration that probably is due to tires. What concerns me is that I feel the vibration coming out of the floor, and especially from the rear.

What I've done so far:

- Took the car to the Mercedes dealer
- Had them replace the S500 lettering on the back with S350, cost me 33 EUR for this. It still amazes me that people still do this.. It's an S350, not a 500.. you can hear the difference...
- They replaced the rear flex disk, it was 'somewhat' old, but not cracked/frayed, tbh I expected to see a destroyed flexdisk with hairs coming out of it. Unfortunately, I didn't.
- They said the front flex disk is in perfect condition and is fresh, no reason to replace



amazing cars these things are..


no wood wheel, but got Harman Kardon


parked behind my venerable E38 M62TU44 w/fresh VANOS, and rebuilt frontend timing drive (thanks BMW for plastic tensioners and single timing chain!)


They also said that:

- engine mounts are 'collapsed' - not cut, but 'sagged/collapsed'
- transmission mount is also 'collapsed'
- rear subframe to body mounts are 'old' and 'tired'

Now, the question:

* If the engine/trans mounts are the cause of this, wouldn't I feel/hear this vibration at 95KM/hr? Why does it start at exactly 100KM/hr and carry on beyond this?
* In my extensive experience with BMW, an engine mount/trans mount will result in some "non-smooth" knocks/feelings of motor against chassis, there's nothing like this here. If you drive the car below 99KM/hr, you would never know there is anything wrong with it.
* Could this be tires/rims? I will take the car to a very good balancing shop (cured my E38 of vibrations after nobody could) later this week to do a cross check on the wheels/tires.

Have another 2 weird issues, will list them here but the priority here is the vibration..
1. Engine oil dipstick pops out after a day of driving, dealer thinks the O-ring on the dipstick isn't making a tight fit. I don't buy it, seems like cyclons or something engine vaccuum related, although I would be sure that this would trigger a check engine and/or weird behaviour. Car runs perfectly and very efficiently, with suprising power. Acceleration 0-120KM/hr is an exact match for my 2000 740iL V8 with VANOS, actually a pretty fast car. we tested this..

2. Backup reverse camera, sometimes, when engaging reverse - the screen shows up, the top line of text is a BIT blurried, but still readable - bottom line on the screen (selectors on how to park) is there, but screen is black - and stays black. After a couple of hours, it will work fine again - and with perfectly clear text on the screen. I read about the cable causing this, but I'd assume this would be a permanent "fail" situation and certainly wouldn't bring blurred text on the display.

Generally I feel that this car will be great - 10L/100KM economy, lots of power, and that Airmatic is just amazing. Blows away the E39/E38 in terms of handling, I still can't believe how level this car stays on curves and mountain roads. Looking forward to a great relationship with this great forum & my new-to-me W221

 

Hi and welcome to the forum.

Regarding the vibrations, if you search you'll find a few threads on the topic. The summary is: vibration on low speeds or when engaging in gear is caused my transmission/engine mounts or gremlins .. vibration on high speeds (above or around 100 km/h) is usually caused by wrong tires or even by the rims that took some beating.

 

Sound like trans mounts but check the engine mounts too, common issue in most MB at your mileage, nothing serious.

 

Thanks guys, will start with a detailed check of the wheels & tires first & post back any updates

 

id def start w a fresh balancing of the tires or fresh tires if needed. Could be bent rear wheels, although if u feel a slight vibration in the wheel u have a bent front too. The w221 isnt like the bmw when u know the rim is bent right away u wont get the traditional wheel shake, you will get a very ligfht shake as there must be some rubber bushings keeping it less noticeable.

 

If mounts are collapsed I would replace them. Also start off with a good wheel balance and 4 wheel alignment. These are VERY expensive cars to fix if something big goes wrong so I would find a good independant shop that can work on it if needed. Dipstick popping out could be a worn o ring but may also be PVC or other component causing too much crankcase pressure. Spend 50 cents on a new o ring an see of that fixes it.

 

+1. I also recently bought S350 but lifted model (2010). Same story with dipstick, had freak me out. New o-ring fixed the problem. Old one was a bit compressed and very hard.

 

That's normal at his mileage of 64,000 US miles>?

 

Congrats! Nice car

If you engine mount and Transmisison mounts are bad, these can cause the issues you are experiencing at high speeds! I would change these right away. These aren't too bad to do either (if you are handy)

I would start there. This has to be done regardless. Once that's done, test it out then go to Balancing tires.

I always recommend addressing KNOWN issues/Safety issues or issues you cannot live with. Whatever you do, never EVER fix/address if you are not 100% sure it's the cause......trust me, with these cars, your wallet will hate you.

I also recommend getting used to living with little quirks and issues with these cars. NOTHING is perfect. And also getting to know these cars well and doing as much as possible yourself, having other people maintaining/fixing these cars put it into "would rather not own" category for me. Just not worth it.

 

100,000 KM & 5 1/2 years later....

Rating: 9/10

Positives:
* Beautiful, aerodynamic body
* Very good high speed stability
* Excellent braking especially in panic stops
* Very fuel efficient powertrain
* Excellent soundsystem (HK)

Negatives:
* Balance shaft was a bit.. ridiculous. I've never opened an engine before on such a new car.. pff..
* 7g tronic failure was also. . not inspiring..
* steering rack/servotronic feels a bit, non-heavy duty (for me), I would have preferred RBC W140 style, but that's just my opinion
* Rattles in interior that are very difficult to trace/fix

My experience:

* Balance shaft caused check engine at around 121,000km, replaced intake manifold at same with new unit, no engine damage as I handled the balance shaft case as soon as I got the CEL
* driveshaft ended up being replaced completely, this fixed the vibration issue at >100KM/hr,
* harman kardon amp failed a year ago, found a good company in NL that rebuilt it
* transmission failed & was replaced w/MB remanufactured unit (neutral, no gears) at 140~,000KM,
* replaced front/rear control arms upper/lower & all subframe mounts at 180,000KM
* replaced steering rack w/new MB part at 175km or so, was harder to turn the car right than left, this was a 5K+ "incident" as I ended up replacing the entire front end (100% of all moving parts) before I reached the steering rack.
* radiator at 181,000KM
* A/C compressor at 170~ or so, seized and this was a bit expensive as garbage went throughout the entire a/c system
* driver door window regulator at 150~ or so, started clicking, this was a preventative maintenance job as it would have failed eventually
* I'm sure many more than this as well, these were just the most interesting thus far in my experience

rest is regular maintenance, I change oil every 10,000KM with 5W/40, and replace automatic trans fluid every 30,000km or so

also had to replace rear windshield to the tune of 2700 EUR, after a huge crack appeared square in the middle of the glass, that was weird, never did figure out how this happened

the car has some rattles in the dashboard behind the instrument cluster, as well as a nice squeaky sound when the drivers' seat is positioned low, so I just keep it at mid height

I reset the trip/economy meter 30,000KM ago, right now I can tell you that for the last 32000~ KM or so, the average fuel efficiency has been 12,4L/100 (19 miles per gallon) MIX highway/city. I don't drive the car hard.

I run 18" 255/45/18 + 275/40/18 Michelin Pilot Sport 4's, and get about 20,000KM before they're at the 4mm wear point.
I also discovered that you can drive this car in heavy snow with proper snow tires, I used the Nokian WR A4 for a few years, then switched to the Pilot Alpin 5 (235/55/17) and I feel it's better with the Michelins.

Brakes I tried to use Textar once, and immediately went back to original Mercedes parts.

Every single spare part I've ever put on the car has come from the dealer, brakes, control arms, bushings, everything.

I'm happy about the car, so happy in fact that since then I bought another one (W221 S350 shortwheelbase , and an SL R230 again with the M272 engine

Total costs so far (repairs & maintenance) are approximately 26,000 EUR for 100,000KM

I believe that the next 100,000KM will cost significantly less, as I won't have to think about the balance shaft, nor the transmission. I'm sure I'll be thinking about the trans again after 300,000km but that's 5 yrs away.

One note, I wish that when I was buying this car, I had spent 15,000 EUR more, and bought one with 40,000-45,000KM max, and preferably newer (>2009). Live and learn, but still, it's been fun