[OMEGA412]

Hey everyone, my 2008 335i has recently developed a strange clunk. The noise is only present at low rpm <1800. It makes a single clunk when putting the engine under load. I'm leaning towards it being the stock dual mass flywheel as it has 90k on it. And it sounds like it's coming from in front of the shifter.

Edit added video
https://youtu.be/SlwRiHT1WuU?si=DW4V2PKgdK2KE9gA

[335i54n]

check ur driveline mounts, when dmf fail they usually just rattle

[AWD Addict]

Mounts was my first instinct

[OMEGA412]

Originally Posted by 335i54n

check ur driveline mounts, when dmf fail they usually just rattle

Originally Posted by AWD Addict

Mounts was my first instinct

Sounds good I will check the mounts.

Here is a video of the noise, it only ever does it in low rpm with decent amount of load
https://youtu.be/SlwRiHT1WuU?si=DW4V2PKgdK2KE9gA

[335i54n]

if you dont actually feel it, it might be tough to locate. doesnt sound too bad (or like its mounts/movement) so just a lot of checking

[OMEGA412]

Originally Posted by 335i54n

if you dont actually feel it, then it might be tough to locate. doesnt sound too bad (or like its mounts) so just a lot of checking

Yeah I can't feel anything, it just sounds like it's coming from in front of me. That's why I was originally thinking flywheel. Also if I hit the clutch in and back out it will make the noise everytime. My biggest worry was it being something in the engine. I read a forum post from an m3 owner complaining about a similar sound, or at least similar conditions to cause the sound as he didn't post a video. Apparently it ended up being early rod knock.

[335i54n]

does it have a light rattle at idle and push clutch in goes away? that how both my dmf failed (internal damper), could be urs is worse than my experience. more of a click/clank imo so there will be witness marks of the 2 parts touch, i would try a shop lift and hope it does it in the air with no load

[OMEGA412]

Originally Posted by 335i54n

does it have a light rattle at idle and push clutch in goes away? that how both my dmf failed (internal damper), could be urs is worse than my experience. more of a click/clank imo so there will be witness marks of the 2 parts touch, i would try a shop lift and hope it does it in the air with no load

My flywheel rattles bad. I've known it needs replacing. The clunk noise is just new. I only get the clunk under load tho.

[335i54n]

dude, come on. look up the internal function of a dmf and u understand, cant neglect issues so Long that they create more

[suspect]

Originally Posted by OMEGA412

My flywheel rattles bad. I've known it needs replacing. The clunk noise is just new. I only get the clunk under load tho.

The rattle/chatter at idle that goes away when clutch is depressed is common in cars with N54, apparently people have it even after dealer fit a new clutch and flywheel.

I cant tell the noise from the video but does it sound like this?

is it a noise that sounds like something moving back and fourth a bit? This is what I have when I abruptly disengage the clutch at low RPMs and usually first gear. Not a helpful response but I have been struggling to find what it is as well.