SOCAL2015

Hi All - first post here,

I recently purchased a CPO RWD 2015 C300 back in mid January from MB San Diego (Feb 2015 build date). I was really hesitant in getting a first year build but this car was very clean and well optioned with less than 17,000 miles. It is a sport model with 18" AMG rims. Unfortunately, the car suffers from a chassis vibration above 65 mph that has yet to be resolved. The vibration can be felt slightly in the steering wheel- in the front wheel well but also in the rear. It is has a very slight fluttering sound and is rhythmic and also creates a vibration in the rear view mirror. It feels like something is out of round and is present even above 80 mph.

Since I have owned it, the car has spent more than 6 weeks in the shop (more than 3 weeks for the wrist pin repair and other corrections - and almost 3 weeks trying to fix this vibration). When I initially test drove the car, I did not notice a vibration above 65 mph until a few days after I took delivery. I assumed it was from the run flat tires (looked like they were just replaced and new) and proceeded to change them out to a set of Michelin Pilot Sport AS3+ for a better ride (was planning on doing this anyway). The new tires were road forced balanced by dealer and the initial analysis from the hunter machine was pretty good. Unfortunately it did not solve the problem. When I brought the car back a few weeks after the wrist pin repair, the dealer tested a set of different rims and tires from a different vehicle - vibration was still present. They then proceeded to replace the rear half shafts (axles) front engine mounts and rear transmission mount. They claimed it solved it and I picked up the car and it made it worse. They now claim all 2015 sport models do this (BS!). I have not physically seen the previous repair history on the car but have been told be the service advisor that nothing has every been reported.

Over the week end I complained to the sales guy that sold me this lemon and wanted to trade it in for another vehicle only to be told that the car has lost 10K since I purchased it in mid January... The car also suffers from an occasional suspension clunking noise on the left hand side when I enter a drive way (the dealer put over 70 miles on the car and claim they do not hear it). It sounds like a shock mount or sway bar link problem or perhaps the steering rack. All this on a car that is supposed to have less than 17,000 when I bought it??? At this point neither the service advisor nor his manager/director will return by calls to discuss the issue.

Has anyone suffered this type of vibration before that is not a wheel balance issue out of round rim or bent rim? I am thinking it was involved in some sort of accident - like hitting and driving over a curb or center median and I will have the car inspected by an independent shop. I don't think an imbalanced drive shaft or split shaft/axle would be also be felt in the front of the vehicle just in the rear and I have a hard time believing that it left the factory like this... I have been a long time supporter of MB - my family still owns a 1986 560sl from new, I have owned a W204, a W210 (E320), leased a W212 (E350) and have a Sprinter van for the long trips. I certainly will not be buying anymore vehicles from MB San Diego!

Any input or help would be greatly appreciated.

Thanks.

GJC400

You still have a few options. You can continue working with that dealership, and take the service writer out on the highway and show him the shake. You could try calling a different dealership and describing the symptoms to them.
I had a similar shake with a GTI that remained unfixed after new wheels and tires. In the end, I traded it in on my C. I suspected damaged or worn bushings/links. A competent dealership should be able to diagnose and fix this. Your current dealership is telling you there's nothing wrong. I would go elsewhere. Good luck.

ItalianJoe1

Could be driveshaft related, the vibrations through the carrier bearing are in the center of the body and can be felt anywhere.

Is it only speed constant? Meaning if you change gears but maintain 65mph, it stays the same? If so, that will rule out engine/transmission vibrations, meaning it will almost certainly be from the wheels/tires/driveline.

SOCAL2015

Thanks for the reply - Yes it is speed constant. If I downshift or even put the car in neutral at that speed the vibration is still present. If the tires and wheels check out, I would also suspect the wheel hub and bearing assembly (I believe it is one piece) that spins in the knuckle assemble - if it is slightly out of round I would think it would cause a vibration. The car seems fine above 85 mph +

ItalianJoe1

Yes, it could be a wheel bearing/hub, if you've had impacts with a curb it can warp them slightly. Check wheel bearing adjustment if possible (some fronts that aren't 4matic can be adjusted), if you need to you can run a dial indicator on the hub/rotor to make sure it's flat and true.

SOCAL2015

Awesome insight - thanks. The latest is that the Dealer has been told by Mercedes Corporate to closed the case. They had the field tech engineer from Mercedes look at the car when they had it for three weeks and according to him the Dealer replaced even more parts than they should have... According to Mercedes it is normal on 2015 especially sport models and I am not the first to complain about it. The service manager cited some technical bulletin and basically read me a scripted response. Anyone else felt this on a 2015 Sport??? Yes the suspension is quite hard compared to comfort spec. I am not running 19' and can't magine what I would feel if I had that on the car.

Very disappointed at this point. I have reduced the fire pressure to less than 33 when cold that has seemed to help a bit. I suspect they made changes to both shocks and spring rates and subframe bushing stiffness in later models to maybe soften things a bit and help dampen vibration. I have not driven another 2015 sport to compare but all the loaners that I had 2017 and 2018 were smooth but of course were non sport. I will never buy a first year model car again - no matter how good the deal and tis is my last Mercedes - they lost my business. I will try another dealer at some point but according to MB San Diego, the vehicle has been tagged in the system so no warranty work will be covered for any additional repairs - just F#$&ing unbelievable.

ItalianJoe1

That's not right. Call MBUSA customer support, open a case. Tell them you are dissatisfied with that level of resolution, and feel that if the car is truly that bad and there's nothing they can do about it, they should offer you trade assistance into a different one that doesn't have this issue, like the loaners you've driven or a 2019 with the revised suspension.

SOCAL2015

[QUOTE=ItalianJoe1;7456605]That's not right. Call MBUSA customer support, open a case. Tell them you are dissatisfied with that level of resolution, and feel that if the car is truly that bad and there's nothing they can do about it, they should offer you trade assistance into a different one that doesn't have this issue, like the loaners you've driven or a 2019 with the revised suspension.[/QUOTE

Yes that is my next step. I am going to try to get the Service Manager to file something in support of this issue. They cannot deny that the problem does not exist - just this morning on my way to work it was again just horrible- it is like I have my own vibrating throttle plate, steering and seat for massaging purposes... I tried lowering the tire pressure (32 cold front and rear) and it seemed to help for a day or two but it came back this morning in a bad way - so strange.

I noticed that the shocks really stiffened up today- the car was really hard on every surface more so than usual - not sure if these shocks are the " self adjusting based upon your driving style" type that Mercedes had - I think they called them agility control shocks - perhaps they have something to do with it. The ride usually starts out softer and then gets stiffer and stiffer the more I drive anyway.

At this point I have decided to move on from the car whatever the outcome - it is just not worth the aggravation any longer - too much negative energy which is counter productive.

Thanks again for your help and safe travels!

ItalianJoe1

I'd try different tires. The vibration when cold sounds like tires that are flat spotting, but in general the OEM tires are too hard and ride like crap.

SOCAL2015

That is the first thing i did. It has brand new Michelin Pilot Sport AS3+. I kept the original Continental Run Flats that came with the car when I bought it. They have less than 1K miles on them, but were super hard as run flats are in general.

ItalianJoe1

Ah. Strange then. I'd still suspect a driveshaft imbalance or some issue like that, if it's really shaking at speed like that. The 205 is a very stiff chassis, too much so IMO, but the vibrations don't sound "normal".

SOCAL2015

Can a unbalanced drive shaft also cause vibration in the front wheel wells, steering and throttle pedal? I thought it would be mostly felt at the rear. But again I am out of luck with MB San Diego. I will call MB customer support to start a case.

Cyber2017

[QUOTE=SOCAL2015;7457247]I have a 2017 C300 with the Sports Package and the 19" AMG Wheels...I love the car but I seem to have a similar problem at highway speeds. Vibration starts just over 70 mph and continues all the way up to 80-82 mph. It is quite annoying and the vibration can be felt throughout the whole vehicle. I have not been able to go to the dealer yet but I spoke to another MB owner with the same car and he said the same thing. He also took his car to a local MB dealer and after "checking everything" they told him that they found nothing wrong the vehicle. I am still running my Continental run flats and I can already tell that they would not last for more than 15000 -18000 miles, especially down here in Florida. I am going to try and get all four tires balanced first and if I see no change, then I am taking it to the dealer.

SOCAL2015

I find that the sport stiff suspension really transmits any type of imperfection that is going on - just even a slight morning tire flat spot feels like a bent rim at highway speeds until things round themselves out. One independent Mercedes dealer that drove the car really thought my car rode like crap with the current suspension set up... way too stiff for a Mercedes he said...

In an effort to narrow down the causes for the vibration, I am having a wheel shop look at my rims. The dealer (MB San Diego) said they were fine and did a road force balance and all the rims checked out OK (that is not the problem they said). I jacked up the car a few days ago and when I was spinning the wheels I can see that there has been previous damage to both front rims.

On both fronts the outside lip has been worked on and in some areas it looks like the top lip is lower and more recessed than in other parts of the rim. When you spin them it looks like the rim is more oval than round and where most of the repair has been done it can see more tire area (where the lip meets the tire ) than in non repaired parts. I am assuming that is where they were bent previously- curb damage is one thing but I think this is/was more serious.

This is a CPO car and wheel inspection is part of the certification process. Either MB San Diego had them worked on or it was the previous owner, but I am betting that they are out of round. I will know next week.

Again the sport suspension is definitely stiff. I would dare to say that it is probably 50% stiffer than the non-sport loaners riding on 18 with run flats. Does anyone really know??? I had a recent 2018 loaner for another Mercedes I had in the shop so I could definitely compare both my Sport c300 to the loaner at the same time. Physically trying to push down both the front and the back between the two showed a major difference - very little give on the Sport. I REALLY like the way the Sport handles, but the ride is probably too stiff for our "third world" road conditions here in sunny San Diego - they say it is because of our extreme weather... I had to make a run to our wonderful airport and the road was so bad I had to slalom in and out of lanes to try to avoid the holes but there are some that you just can't avoid and man did things come crashing through.

If I keep the car (waiting for MB to respond to my complaint and request for a buy back), I think I might look at changing the shocks or springs (perhaps both) for something a little more forgiving - somewhere between the sport and non sport set up would be ideal. I have new Michelins which I have set to 32 all around which has helped a little. Wish the car came with adjustable dampers.

Cali4niadriver

pinworm

I have the same issue in my 2015 C300 4Matic. Happens around 65 to 70mph. I suspected the after market rims and tires, and am having them swapped out tomorrow (don't like them anyhow) and hope that resolves it..but if you find a more built in flaw let us know. I will see if I have the same problem.

SOCAL2015

Just a quick update. Well after waiting for a resolution for 6 weeks or so, it looks like Mercedes Benz is willing to buy back the car under the CA lemon law - so I can finally move on. I was never able to get this problem fixed - it is not wheel or tire related. The thing just starts to rhythmically vibrate at speeds above 65 to the point that even my interior rear view mirror was useless at those speeds.

Happy to be moving on and I hope no one else is suffering from this on their 2015's. Not sure if I will go back to a C class at this point. If I do, it will be new and have two more cylinders. The four fills its intended mission quite well, but having lived with it for a while, I was never a fan of all the strange engine noises my 2015 seem to have especially at idle - it would more often than not make a ratting/puttering noise when stopped at lights in drive (2017 & 2018 loaners did not seem to do this as much). My car was a February 2015 build (2WD Sport) and I can't help but feel that these early 2015's were really a mess (wrist pin, crackly interior door panels and seals, dash creaks, etc.). Improvements were obvious in the loaners I had so that is a good sign.

I wanted to thank everyone that posted a response to my rant... Mercedes Benz certainly did the right thing by taking this car back. They have kept me as customer going forward. Well done MB!

pinworm

Mine turned out to be the tires. Once I changed them and got thicker, regular Continentals on the stock rims, the vibration went away.

Sorry to hear the OP's problem was more serious.

Cali4niadriver