cruiser02

As some may know, my car is a 2012 Mercedes-Benz S550 with the M278 engine and almost 65k miles. She developed a very ugly sound (metallic clunking / something loose) from the front axle when going over bumps so I booked an appointment at my shop. A week later I take it in.

First day: They've injected and put grease all over the bushings, helped but not much.
Second day: The control arm is pretty bad, $1,100 to replace. No change.
Third - Fourth day: Doing more diagnostics and landed on the top of the suspension strut. Whole strut to be replaced with OEM part, not Arnott. $1,600 with considerable discount included.
Fifth - Sixth day: Waiting for part / techs have time off. I've also let them know about a vibration when stopping and slight shaking when cold start, I suspect motor and transmission mounts. More diagnostics led to collapsed motor and transmission mounts, $1,350. They said these could wait a bit, but I opted to change them anyway since it's more of a pain to coordinate time off and rides to shop and back.

Hopefully by next Tuesday I receive some good news that it's fixed because I'm at $4,000 in the hole so far

Jaap

Holy Guacamole!
$1100 for a control arm? What in the...
If i were you i'd search for a good indy (they may be hard to find though).

BOTUS

brilliant they have 3 but no one in the usa knows the correct names

the front caster control arm is made of aluminum and the bushes self disintegrate leavings lots of slop that should make lots of noise - but as its hidden by the front rad engine cover you can't see it !!!!!

the track control arm - as it controls the wheel's distance apart, AKA "the track" (like train tracks) - hence why we adjust the tracking to get the two wheels pointing where the manu thinks its should be - wears the ball joints a bit

the last one acts as a top wishbone

the resultant mess is the budget way to make a nasty "macpherson strut" almost behave like a decent suspension system


its like NATO - its stands for North Atlantic States of Israel but only three people outside that crooked empire really understands it


'

ChrisHimself

Metallic clunking is metal on metal, the bushings wouldn't disintegrate that early to leave you with metal on metal contact. That points to the ball joints are out, and dry and you could be free-floating the ball joint which would be a HEAVY clunking as the car slams on the suspension arm, or the sway bar end links which would be a lighter rapping sound, although typically they are encapsulated in teflon so it'd be a while before you were metal on metal.

At 65k none of this should be broken TBH. The engine mounts these days are much nicer and sturdy than the mounts found on the older cars. The rubber that holds the hydraulic fluid in works. The trans mount can/should be replaced. I don't like to undercut another man's work but sounds like youre buying MB Genuine parts at full boat and paying $200/hr labor?

I have the same car and everything lasted until about 120k miles when stuff started breaking. Have you hit anything recently? If you crush the ball joint from an impact it can accelerate wear. I'd also check for loose suspension bolts. The mileage is really suspect for MB parts to just give out like that.

nath_h

FWIW, my 2008 needed new motor/transmission mounts at 40,000, I bought the car at 50,000 and found it needed all new front suspension components. By 60,000 I had changed all of them, and the difference was big. No more clunking, no more steering wheel shake. Even though some of the parts looked okay on visual inspection, the ball joints were floppy when inspected after being pulled out of the car. So my point is that in this sample size of one, it is possible he needs new control arms and possibly other components. The cost is another matter. If the op has any mechanical ability, they really aren't that hard to do yourself. $4000 at the MB dealer is unfortunately an ordinary occurrence, and it could and probably will be much worse in the future.

justchangeoil63

Yikes! That really does suck!

As far as what the problem is, it's metal on metal (a few people have already pointed that out). If you can try to just jack up one side of the car and look VERY closely at every part of the suspension. With a noise this prominent, it should be something that you can see & feel.

Unfortunately, you seem to have gone to a "Parts Cannon Shop" (in my opinion) as everyday parts are just seemingly being replaced just to see what happens from what you described. Which ends up in a repair bill like that very quickly. I know it's hard to do things without a lift and all the proper tools, I'm quite spoiled as my dad was a mechanic so we've got tools. But The best way to save time & money on these cars is to diagnose the issue yourself, and if you can fix it. But I've found if you go to a shop and say fix this, not Oh I hear this sound, it helps. (There are some things you should go to a shop for, especially if you don't have all the tools, I'm not knocking anyone who goes to shops though as I'm there often as well lol)

Good luck!!!

JohnLane

Guys we have not driven the car. As such we are unaware of just how big a noise it is.

My 221 S-65 needed lower front suspension arms every 30,000 miles. The ballpoints would be squeaky clunking worn out.

It needed engine mounts about as often.

OP for clunks I reach for all the lower arms first. Be sure the tech also gives it a hard shake at 09:00 on the wheel to check that there is no slop in inner and outer tie rods. Upper ball joints wear out too. Easy to check.

An an alignment done by someone who is familiar with aligning MB must happen afterward.

K-Mac

Do keep in mind - today's models a “Full Front & Rear ‘4’ Wheel Alignment” IS ONLY FRONT & REAR TOE - Directional adjustment !

And ‘S’ class being heavy vehicle - there is no longer Front Camber (or Caster) and no rear Camber to adjust tire contact angles, spread load more evenly. IT IS NOW ONE SETTING TO SUIT SHOWROOM HEIGHT CONDITIONS.

No adjustment to compensate for high cambered roads with excess passenger side edge wear. Wheel squat through extra passenger loads or lowering to improve handling. Fitting wide profile tires. Now no ongoing adjustment to cater for curb knocks.

IT IS ALL TO DO WITH THE EVER INCREASING SPEED FOR NEW CAR ASSEMBLY LINES. STOPPING TO ADJUST SETTINGS - is no longer an option !

Putting onus back on owners to fund costly premature tire replacement.

W221 ‘S’ Class - See Spoiler







AUDI to VOLVO - Experience Of Resolving OEM Suspension Shortcomings (and costs) Since 1964 !

ChrisHimself

oh wow i have very little exposure to the v-12's thats a fascinating bit of trivia!

cruiser02

Thanks all for the replies, it seems that the W221 suspension components are under a lot of stress from the weight. The car is at an Indy shop and not an MB Dealer, unfortunately these are under market prices for the San Francisco Bay Area. I also trust these guys more than other shops and especially dealers. They've saved me a LOT of money when my camshaft sensors leaked into the engine harness and other repairs, so they're not just out to scam me. Could I have made a stink and not pay? Yes, but I chose not to and accept the fact that I'll have new OEM components that should last for a long time.

That being said, I am unhappy about the uncertainty of a definitive answer on what the issue is. It only makes it when driving, I pressed and jumped on it while stationary and nothing. The shop owner (25 years MB exp.) and lead tech (13 years of MB exp.) have been working on my car and I do trust them when they say it is a hard to diagnose issue that is now taking 3-4x as long as anticipated. I'm an engineer by trade and if my projects take 3-4x as long as I planned for, I would take personal offense to the quality of work.

JohnLane

OP ‘chassis ears’ attached to each arm may help to narrow it down but the most sensible fix is replacement of all lower arms. They wear at about the same rate. Thus, one arm is worn the rest are not far from being ready.

cruiser02

Thanks, when it comes to suspension components I don't know much. I did ask about that and they said it is not needed to change the rest of them at this time.

ChrisHimself

I'm in San Jose if you ever wanna pay a visit..

nath_h

I have come to learn that when driving a 17 year old super complicated car, there is uncertainty I just have to live with. Occasionally my car makes an odd noise like a weird tapping sound that comes and goes that is impossible to diagnose, but not really causing a problem either. Other problems have been difficult to diagnose, but I figured out later by chance when working on something else. There is a certain amount of art and not science when it comes to these old cars.

Arrie

Read my last post in “Shock Absorption Completely…” about what needs to be done to properly inspect the ball joints. Anybody claiming joints are good without taking the parts loose has not done the job right.

cruiser02

That’s not an option for me because that bill would be astronomical and simply not worth it. Car drove perfectly fine before and buttery smooth. I’m not going to tell them their job, I just want my car back at this point.

cruiser02

Thanks Chris, the car is currently in San Jose too. I’m in the East Bay, but there aren’t many European shops here so I make the hour drive south when needed.

cruiser02

Good news so far, was told the car is good as new and ready for pickup

Arrie

So, what all was done to it?

cruiser02

What’s mentioned in the first post, nothing additional. The mounts were maintenance and not related to the clunk btw.

Arrie

Well Great Then!!

If the car is back to “as new” condition you did all right things.

Happy Motoring!!!

P. S. In your post you talk about Arnott the way it is not a good option, or at least it makes me think that way. I have used Arnott struts in two cars and I am about to use Arnott rear struts on my current W221. I have not had problems with them.

cruiser02

Thanks! Credit goes to the shop for dealing with this. I simply drove it there and opened my wallet lol

vettebk

Glad your car is operational. The W221 is especially heavy and if you also run 19 inch wheels, the lower control arms take a lot of punishment. I had to replace lower control arms about every 35,000 miles. At 95,000 miles; I bit the bullet and bought a full OEM suspension component kit from FCP Euro with both sets of upper, lower forward and rearward (Lemforder components) control arms. I had my Indy install it all, and did an alignment. He also found a couple of my alloy wheels a little bent and once those were refurbished; the car drove remarkably better (and it was pretty good before). I wish they made the alloy wheels out of something a little harder to survive the road hazards; but I bumped the air pressures to 40 psi to give me a better chance going through the potholes.

BenzV12

Nice to see everything is sorted out for good
S Class is the best car to me when everything works neatly

cruiser02

Well that didn't last long. The noise came back the same day and sounds even worse. They've been looking at it for two days and no news yet. I uploaded a video here: https://imgur.com/OFW2jkU

It's been almost two weeks, a bit concerning but still have hope. For the little bit that it was fine, it felt really good to drive with the new mounts.