cls450 2019

Opinions about this knock?
cls 450 2019 4 matic.
the knock comes from under the car i think engine to transmision

MikeJohns

Hi, this is exactly the same noise as I have on my 2019 CLS450. It started very faintly at 30k miles, only I could hear it but now at 45k miles it's pretty audible. I'm praying it's not internal eg small ends etc perhaps it's an ancillary so water pump or alternator etc I believe that some ancillary items are electrical rather than belt driven so that will help isolating (if I knew which was which of course )
There is another post that turned out to be a hugely expensive engine swap as it was small ends and as noise is getting worse I'm going to take it to MB (or poss specialist) as soon as hols are over. Will update post with the result, please let me know if you find anything out,thanks.

cls450 2019

Mb dealership says it s nothing wrong with the car, my mechanics told me that engine sounds good nut the knock comes from gearbox, next week i will go to a gearbox repair shop and i will make an update. Keep me in touch please

MikeJohns

Interesting, I had the same response from MB but to be fair to them it was pretty quiet then, I could hear it as I was so used to the normal sound. But now it's louder and anyone can hear hit whilst the engine is idling.
I hadn't considered the gearbox but will be interesting to hear what your mechanic says, mine is linked to engine speed, increases frequency as you rev the engine in neutral l, so guess it's an input gear or bearing etc in the gearbox.
Unfortunate I've recently moved and don't have a MB specialist near me so won't be able to see them for 3 - 4 weeks. Will book myself in an update you then.