Just thought I'd share.

Just before the holiday break, I decided to bring my car in for a service.

I've been noticing a rumbling noise and vibrations from my car whenever I accelerate hard. Under non hard acceleration, everything seemed fine though at high speeds though, around 160kph and up, the rumbling and vibration gets very evident.

At first I though there was something wrong with my wheels, maybe there was something in the back of my trunk or my rear bushings were broken but when driving over rough roads, everything felt fine and it only happened under hard acceleration or when driving fast. Just to check, I unloaded everything, took it out for a spin again and the sound and vibration was still there.

So I realized it wasn't anything of the norm anymore and took it to the dealer. Turns out, it was caused by worn out engine mounts! I only have 30,000km on my odometer and I already have to change the engine mounts! I'm quite surprised that it got worn out so quick. Anyone else experienced this?

Apparently the worn out engine mounts were transferring the engine vibration throughout the car. I feels like your wheels aren't balanced in terms of vibration and the rumbling noise sounded like it comes from the rear. If anyone else hears or feels this, make sure you give your engine supports a good check!

Hope this helps!

Btw, are there any reinforced or strong engine mounts out there that can be purchased? Or is the car still too new and my problem still too unique for someone to come up with a solution for it? My car's out of warranty and the dealer is charging me 288 USD for the front mount and 110 USD for the rear mount. I'll need to replace 2 for the front and 1 for the rear. That's a total of 686 USD just for engine mounts! Whoa!!

 

Your most likely problem is the rear gearbox mount (or engine mount as Benz call it. The parts are cheap. Sounds like the dealer making a few bob.

 

Glyn,

Is there something Albert can visually check to see if its the enigne mounts or the rear gearbox mount. Nothing like spending the money to fix a problem only to find out that the problem is still there.

 

Indeed! Is there anyway I can personally visually check the damage? I would greatly appreciate it!

 

Drop bottom engine cover & inspect these for damage:



Look at rear of transmission & look at this for damage. Put hand on rear tunnel while driving & you should be able to feel vibration



Check flex discs on each end of the propshaft for damage/cracks.

 

Wow! That's real cool! How'd you get those diagrams? I was able to get the part number from the dealer. They said these are the ones that need to be replaced. 204 240 0917 and 212 240 0418. Would you know exactly which parts those are?

The dealer said the car can still be driven. True? I need to use my car since it's my everyday car but I wouldn't want to this problem to cause damage to other parts of my car.

BMW has www.realoem.com to get access to all the part numbers and such for BMW cars, does Benz have a similar website where I can access and find part numbers for parts?

 

I had the same issues. They replaced all my mounts, front engine, rear tranny/engine mounts. It took forever for them to figure out what the problem was. I only has 20K miles on the odometer at the time. I have not had any probelms since the put the new ones in.

 

Aggressive.....any idea how your motor mounts were so worn at 20K miles....

I'm assuming that your screen name tells the story.

 

How many pieces of each did they have to replace? Cause my dealer is telling me I have to replace three. Is that all of them or is there more?

 

How many pieces of each did they have to replace? Cause my dealer is telling me I have to replace three. Is that all of them or is there more?

 

Oops. Sorry for the double post!

 

If you drive on worn engine mounts, I presume that puts greater stress on components such as cats, drive shaft?

Just wondering how long I can drive with them.

 

Not a good idea to drive with damaged engine mounts. The excessive vibration can damage or knock loose electrical connections, and those are a pain to diagnose and fix. I recommend fixing it ASAP.

 

Got the engine mounts done. two issues have come up.

1. I'm smelling petrol in the engine bay. i did replace faulty thermostat.
2. Does Engine Mounts require two bolts? see photo.



Empty Engine Mount hole.

 

The engine mounts of my C250CDI 2012 gave way suddenly last Thursday, rendering the car un-driveable.
The car has done 16,000 Kms in 6 years. The car was running smooth till all hell broke loose suddenly!!
The Local MB Service is replacing all three mounts - 2 at the engine and 1 at the gearbox at a phenomenal cost !!
I had a look at the pictures of the parts posted by Mr. Ruck.
Wonder why these have to cost so much. And are these parts designed to fail at a specific time period ?

 

Well... the term:

... is fairly subjective. And without an actual number, it'll be difficult to justify or determine high or low. It appears that the 2 engine mounts are approximately $170; whereas the transmission mount is approximately $60... So that's $170 + $170 + $60 = $400 just for parts... How much in labor are they charging you?

If they are designed to fail, it certainly isn't at 16,000 KMs. But judging by your description of catastrophic failure and the car rendered undrivable as a result, they had to have been subjected to a considerable amount of stress and strain just prior to them failing.

 

Many Thanks for your response. The car was delivered today after the mounts were changed. the Front mounts costed $216 each and the rear mount costed $85. That sums up to $517 for parts. Plus the Labor was $136. [ A radiator delivery hose was also replaced at additional parts and labor cost.] The inflated spare part figures are for the local taxes and customs duties we pay in India.

MB must consider the weather conditions in India which effects rubber and plastic parts of cars. I believe they should homologate these critical engine parts for our environments. I have heard that the common grouse amongst Indian MB owners is about replacing worn rubber/plastic parts. They all start falling apart in the 5-6 year period !! The Service Engineer pointed out to an ML on the shop floor this morning, whose engine mounts gave way just like my car.

As regards stress and strain. The failure happened early morning at 6-30am while dropping my son off to school. Car with just two of us riding. Accelerated over 2000rpm to catch the green signal near home on an already warmed up engine. The mounts gave way right at the signal crossing....

 

I did not see a location in your profile and yes, the prices I posted are for parts via a U.S. based MB dealer. You can find them for even less than what I posted on Amazon as one example. Although you'll have to find a seller who ships to India and even then, after adding a shipping charge, who knows how much they will end up costing.

That labor charge you paid seems very reasonable for the job done. Based on what I can find online, that job will run between $224 and $563 here in the U.S.

I would venture a guess that they do. The same way they only offer some features/options in certain regions but not in others.
I am not sure what weather conditions you may be referring to but will assume you're referring to India's "high temperatures"...

I would venture a guess that every part is designed, manufactured and tested under a wide range of temperatures. Including extreme heat. Specifically, when it comes to engine mounts, I'd imagine that hot weather and high temperatures is not much of a factor because it does get fairly hot in the engine bay, whether the car is in India or in a somewhat cooler region of the world. I mean, the exhaust manifold itself will reach temps of several hundred degrees Fahrenheit. And so an engine mount is not likely to suffer premature failure due to air temperatures of 110°F, even 120°F (highest recorded temperature in India in May 2016 was 51°C = 123.8°F).

Well, under these particular circumstances where engine noise and vibration must be severely reduced or eliminated, the choice of material to incorporate as part of an engine mount is extremely limited.

And unless you are suggesting that other car makes use neither plastic nor rubber on their cars, I don't see how such a complaint would only be common among "Indian MB owners"!