gfmohn

Yes, all pre-mid-April 2015 C300 have the issue. Any M274 built at the Infiniti plant in Dechard before serial number ~43000, or built in Germany before roughly serial ~400000 could develop the problem. (My engine was built in Germany.) New wrist pins went into production engines starting April 20th. There is no way anyone can tell whether all of the potentially defective engines will eventually get the symptoms.

Opinion seems to be divided about whether the cylinder walls will be damaged, if an engine with the rattles is not repaired. It seems unlikely that any owner will drive a luxury car that sounds like a diesel long enough to find out.

Of course, you can get the wrist-pin issue fixed! You can always replace the engine. This doesn't necessarily mean a new engine. Now, there must be lots of wrecked C300s, with undamaged engines (made after 04/19/15). This was not true back in 2015, when I was dealing with my C300. I'm sorry I can't give you any prices for wrist-pin replacements.

voltdriver

While what you said makes perfect sense, in reality what people get from the dealer are always "I think it's fine" / "There is no problem" / "Nothing we can do about it"

Jack_88

Heck, mine's a 2018, and I swear it sounds like a diesel when I idle through the drive through with the window down.

gfmohn

Try to find a better dealer. My dealer initiated the very expensive wrist-pin replacement on their own motion. I had not heard the tell-tale noise myself; i had taken my car in for the wind-noise problem. The service supervisor and I went for a test drive, and it was he who stated that I had the wrist-pin problem. Of course, to find a better dealer, it helps to live in a major metropolitan area where there are several M-B dealerships in competition with each other.

voltdriver

By any chance you said a good dealer you meant MB Boston

gfmohn

MB Westwood

charmz

Anyone in Canada have this done?
My car just came back from the repair and I am hoping the noise is gone!

The dealership where I bought the cpo car denied the issue existed and told me the vin was not affected.
I took it to a second dealer for another opinion and was told they cannot hear any abnormal noises and did a software update for me.
Its not until I went back with these videos and a copy of the TSB until anything got done...

(Outside mounted camera - Listen at 0:45 and 0:53)

(Camera from car interior - Showing tachometer)

Musafeer

TSB? Also what did they fix? I ended being told that it is normal sound, they did a software update, which honestly made it a bit worse and the car shifts a bit more aggressively, but the noise is still there.

C300949

So I bought my 2015 c300 luxury on November 2017 with 37k on the clock. After driving it 1k miles the turbo fails. I take it to the mb dealership for warranty work and they fix it I ask about the noise coming from the engine that sounds like a tractor they tell me it’s normal and that it’s just the injectors ok then it the “injectors” fast forward to last week I’m driving the car to work and it looses all power starts smoking and I hear a rattle in the exhaust metal hitting metal.i have the car towed to the same dealership @58k. out of warranty now and I’m told I have catastrophic piston failure on piston 1 Now I started doing research and my vehicle fall under the dreaded wrist pin failure and now it needs a new engine I’m told that it would cost 6k to remove the engine and diagnose the failure. POS I owned my 2008 c350 for 9 years and it was the best car that I owned.How do I reach out to mbUSA? Any Advice would be greatly appreciated.

C300949

Repair bill for engine replacement

Harold1898

This issue is worse than the C63 problems pre the facelift if 2012. MB really needs to do something about this. I feel for all of the affected people.

Uumode

Is this the sound you get? My clicking noise is heard from transmitted sound through the left exhaust on a C300 facelift


Idle on cold engine for first 3 or 5 mins. Then noise goes away.


Brand new, 4 months old, 2,200 miles.

ItalianJoe1

The noise is most noticeable on engine decel, unloaded, and is only present in very few early cars. Most are misdiagnosis cases of other engine noises. My 2018 GLC is very noisy but they all are, you don't hear it in the car, and that's what MB says is "normal" so I don't worry.

The Best or Nothing

ItalianJoe1

That sounds like an exhaust actuator moving back and forth. Not engine noise.

Kiev1979

i have the same problem exactly how you describe and i took it to the dealer 3 times already. Even leftnit ivernight so they can hear it in the morning and they just say nothings wrong