As our M276 W205s age, motor or engine mounts seem to be a common thing to need replacing.
This thread is to try and collect some data and compile some research on our mounts. Im not affiliated with any of the vendors.

Failure mode and symptoms:
Driver side typically fails first because of how the tq applies and twists that side of the motor up.
Mine initially presented with a leak of hydraulic fluid (black) draining down the mount and chassis frame. (take a look when doing oil change from bottom)
Vibration at idle present that doesnt get better after changing plugs. (mine seems to be worse when cold but as the rubber/fluid gets warm its better)
Have heard others report a knock sound under shifts or acceleration.
Final tell is if the motor moves and "jumps" when holding the brake and applying some throttle.

These symptoms gradually progress, I had the leak probably more than a year ago and the vibration now is to the point where a passenger notices it when stopped.

Options:
OEM seems to be made by Corteco.
Available on FCP for decent price, but there are two styles of parts. ($105-165 each based on where you source them)

Driver (Left) Side:
2015 C400 part # 205-240-10-00
Looks like this and is used on C400. E400 and E450 (2015-2018)

2016 C450- 2018 E43/C43 call for part # 205-240-49-00 Which EPC shows as discontinued.
FCPeuro references 253-240-24-00 on a C43 which EPC shows as fitting GLC43 2017+
Finally EPC calls for 213-240-21-00 on 2017-2020 C43 and E43.


There is a good chance all of these are the same mounts with different fluid fill/valving to accommodate lower NVH on E class or maybe more torque output on different models.
Is one better than the other? IDK, but talking with a MB mechanic he replaces a LOT of C43 mounts across all years so it doesnt seem any last longer than others.

So this brings us to aftermarket options.
On some MB models the black series cars came factory with upgraded mounts, im not aware of this option for the W205.
East coast euro used to make poly mounts for MB but I believe they went out of business.
https://mbworld.org/forums/w211-amg/...ns-mounts.html
Similar company Creative-steel also offers a poly mount for older models.
https://creative-steel.com/product-category/mercedes/
I have reached out to their MB specialist and they have confirmed they will work on a upgraded mount for the C400/450/43, ETA this summer. Ill see if they can do a group buy on the first set.

Because of the placement of our mounts, and the fact that they dont seem to last more than 50k miles, id like to do this replacement only once.

 

If they fit C400s, sign me up for 2 sets of they make them this summer.

 

We just wanted to chime in and say that we have purchased a set of engine mounts for measurements. Our hope is that these mounts are similar in height to the W204 mounts and have the same dimensions where the engine mount meets the bracket on top. If that is the case, we essentially could use our W204 pin (top part of our mount) and we would only need to manufacture the base. If that is all that needs to be done, we could release these mounts much sooner than summer time. Once we receive them I will post an update on our findings.

 

For those voting "do" or "don't" need mounts, could you please comment on the thread with your mileage, and if you've brake boosted or rev'd with your hood up to actually see if your motor is hopping?

78,000mi for me and I have a noticeable drivers side lift when brake boosting

 

Ok guys we received the engine mounts and unfortunately they are not as easy to manufacture as we were hoping. They are very similar to the W204 mounts however the mounting points are not parallel. The base is angled which makes manufacturing a little more difficult. I will try to push these along but to be safe my estimate for release is spring time. Let us know if you have any questions.

 

my car was tuned. replaced at 28k. launched ran it pretty hard but well maintained. was one of more heavily modded 43s. drivers side leaked first then once passenger side leaked I replaced. warranty covered it. This car needs upgraded mounts.

 

Thank you everyone for the insight. We are working to finish up the M157 mounts and these will be one of the next mounts we design.

 

Did anyone DIY these mounts yet? At what mileage? Stock or tuned? What has to be removed in particular to get to both of the mounts?

 

hmmm, no one yet, no one other than forum member star4life had to replace their mounts yet?

What about a different question, for those who still have their OG mounts, how much mileage does your car currently have?

 

I have heard, but cant confirm yet, downpipes are removed to R&R the mounts. Some have said turbos come out but i was quoted 4.3hrs for both mounts, so I dont see that being the case. Expect 6hrs for DIY in garage.
I have 76k on OEM mounts, if i grab the intake pipe (metal BMS) i can lift/flex the driver side of the motor but not passenger side.

@Creative Steel any update on the mounts?

 

The mounts are coming soon! We had a couple fitment issues, but we got those fixed and are now just waiting on parts to come back from anodize.

 

Thanks so much forum member MatthewJ for your reply to my post, do you mind also telling me if ours cars having vibration in sport+ on the steering wheel and can be felt in the front passenger seat and driver seat is normal behaviour or could it be my mounts? Is it possible a bad transmission mount could also cause that vibration? I understand transmission mounts are way easier to replace but are you still on OG transmission mounts as well? Thanks again!

 

Sorry I forgot to mention the vibration seems to be only there when idling as long as the vehicle rolling or accelerating it doesn't seem to be there or at least I didn't notice. Thanks! I also notice the vibration is more severe when I bank the vehicle to one side, it is not a huge difference but noticeable.

 

Still on original trans mount. I may replace it while im in there if its easy to get to.
Idle vibration is what originally made me look into needing new mounts. Sport+ does increase the trans pressure and up the idle rpm slightly so maybe its making yours feel worse with that.

 

I really appreciate your reply!

Do you notice that the vibration is stronger and can be felt even in the passenger seat if you bank the vehicle on one side? Or for you it is consistent no matter where you vehicle leans on?

I heard transmission mounts on our cars are super easy to get to and takes less than 30 minutes to replace so that is good.

What about engine mounts, you mentioned it might take 6 hours to replace it but can both engine mounts' condition be checked by jacking the vehicle up to see if replacement is necessary? If so where about should we look?

Appreciate your help!

 

Im not in my passenger seat so cant comment on that. First post goes over some things to look for. For mine the vibration is much less if not completely gone once the mounts have gotten hot (oil temp 190F, trans 160+).
You can put the car up and look for the black hydraulic fluid to be leaking down where the mount is.
Most shops are going to want to replace them in pairs.

 

I see, I mean the vibration intensity in the passenger seat is the same in driver seat or you can just put your hand on the passenger seat and feel it (in my case)

In my case I find it weird that the vibration is more severe when engine is warm or that inside and outside temperature is warm which is opposite symptom of a bad mount I think?

Thanks for this information will try to check that, that way.

Makes sense since everything is already out might as well.

 

Had the mounts changed in my C400. Probably did too many digs and too much brake boosting on rolls lol. Pretty sure they dropped the subframe as my alignment toe was off evenly on both sides which means the subframe shifted. Looking from underneath I do think I could have done it but didn't have the time. They did charge $2k so probably should have just done it myself lol. I am interested in these solid mounts though, would definitely help me with brake boosting.

Side note, I saw your post on dragy MatthewJ, I also am running a JB4 E30 C400 and my 1/4 mile and 60-130 times are pretty close to yours but not quite there, but your 60-130 is a full second faster and I need to know why lol, I really want to push this car more as I believe it can take it. Are you on a custom map6 or map5? Also do you have instagram? Would be easier to message. Thanks.

Ah, also I'm in Central Florida also, UCF area.

 

Thanks for chiming in man, mind me asking the mileage on your ride?

 

Got it done around 80k I think. Don’t remember exactly.

 

I see, thanks for your answer

 

Any luck getting the C400/450/43 community some upgraded mounts?

 

I am also waiting for these to come out. I would like two sets for both cars.

 

Quick question, does any of your cars vibrate (quite a bit, felt in the seats) in sport+ when doing full lock to the left or full lock to the right when idling at a stop? Reason asking is because if I ease the steering wheel a bit the vibration lessen.

 

We have the OEM mounts on hand. However they have taken somewhat of a backseat in our R&D lineup. We do not have an estimate on a release date at this time, but we are hoping by the end of the year!