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When people complain about dmf (flywheel) noise - what are they complaining about specifically?

Clint Beastwood

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#1
Just wondering - the flywheel on the FiST seems really noisy and I've finally gotten used to it, but I noticed when coming to a stop below ~10mph I hear a whirring/thunking sound from the front that doesn't seem to relate to engine RPM, just to wheel speed. I checked the CV boots no tears or anything - with my RMM installed its *very* noticeable, without the RMM its there but very faint, with the stereo on I really don't hear it. Does not make a difference clutch in or out - I am just wondering if it's normal. I have not been able to capture the sound on a recording, and sitting in the passenger seat it really isn't audible.
 


Business6

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#2
I have had what sounds like a card in bicycle spokes coming from the passenger side that's super annoying. It's speed dependent but not audible at all with the windows up. I've asked every mechanic who's worked on my car about it to no avail. The sound has persisted but not worsened for the nearly two years of owning it. Sure as hell hope it's not the flywheel
 


OP
Clint Beastwood

Clint Beastwood

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Thread Starter #3
I have had what sounds like a card in bicycle spokes coming from the passenger side that's super annoying. It's speed dependent but not audible at all with the windows up. I've asked every mechanic who's worked on my car about it to no avail. The sound has persisted but not worsened for the nearly two years of owning it. Sure as hell hope it's not the flywheel
I *think* the DMF sound is mostly the clack-clack noise we get from engaging gears, or when coming back on-throttle after coasting. What I get is a quiet but very mechanical wah wah wah rotating whirring sound when coming to a stop. It's not severe, but with an RMM it sounds really gnarly. With the stock RMM reinstalled I can hear it but its not loud enough for anyone else to notice. I didn't notice it really with my exhaust installed, but now that my car is quiet like a dustbuster it's very notice-able.
 


Intuit

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#4
On the actual topic of the title...

Start it up cold.
Here knock-rattle.
Depress clutch.
Knock-rattle goes away.
Release clutch pedal.
Knock-rattle comes back.
Knock-rattle dissipates as the engine warms up.
Knock-rattle disappears completely if the engine runs smoothly.
Low RPM, low or moderate or even high speed/RPM 1 to 2 shift can result with a loud head-turning CLACK as you release the clutch pedal.
The clack can be inconsistent in occurrence. You can avoid the clack by smoothing out your engagement with a *tiny* bit of slip. As time goes on, it becomes more consistent and more and more audible at three engagement. The larger the ratio jump, the higher the potential for jolt on engagement.
Note, this is different from the clickity-clackity shifting noises that you get while moving the shifter on OEM fluid; which is normal and not concerning.


Inspecting and Confirming DMF (removed)...
https://www.bing.com/videos/search?...DEE4AA1279F42BAB5861DEE4AA1279F4&&FORM=VDRVRV
https://www.bing.com/videos/search?...297F9FDC3467F81AC6CA297F9FDC3467F&FORM=VDQVAP

DMF Knock-Rattle Noise...
https://www.bing.com/videos/search?...F02D1A9E21A03D41BCC5F02D1A9E21A0&&FORM=VDRVRV
https://www.bing.com/videos/search?...37EAB40CA4DD329B1DD437EAB40CA4DD3&FORM=VDQVAP
https://www.bing.com/videos/search?...5F02D1A9E21A03D41BCC5F02D1A9E21A0&FORM=VDQVAP
End-stages...
https://www.bing.com/videos/search?...C71717A2D89D6CE4F63FC71717A2D89D&&FORM=VRDGAR
https://www.bing.com/videos/search?...7579FEAEF07C09AD5D6E7579FEAEF07C&&FORM=VRDGAR

DMF to standard Flywheel Conversion...
https://www.bing.com/videos/search?...6F32100600E4D0A4DAA86F32100600E4&&FORM=VRDGAR

More Info...
https://www.bing.com/videos/search?...9781388E9C9D76957C1E9781388E9C9D&&FORM=VDRVRV
 


FiSTerMr

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#5
I *think* the DMF sound is mostly the clack-clack noise we get from engaging gears, or when coming back on-throttle after coasting. What I get is a quiet but very mechanical wah wah wah rotating whirring sound when coming to a stop. It's not severe, but with an RMM it sounds really gnarly. With the stock RMM reinstalled I can hear it but its not loud enough for anyone else to notice. I didn't notice it really with my exhaust installed, but now that my car is quiet like a dustbuster it's very notice-able.
Yup, that clack is the same as I hear. According to EVERYONE on this forum and reddit, the dmf is to blame.
 


Jerickson88

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#6
I know that on my SVTF, I had replaced the DMF with a one piece aluminum and the car revved like a street bike (in my own world) but sounded like a helicopter at idle from clutch chatter.
 


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#7
I just got the Mountune RMM installed yesterday and my dual mass flywheel clack-clack got a lot worse. I'm just going to learn to tune it out, I suppose. I also got the symposer delete and the extra quiet might contribute as well.
 


Intuit

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#8
Yeah I'm to the point that IDGAF. I'm going to just shift normally. I'm now beginning to hear a tid bit of clack releasing in 4th. I've been to the dealer twice about it and am done wasting my time. First time they couldn't reproduce the problem... which is believable. But I heard it the moment I started to leave the parking lot. The second time they replaced the axle shafts; and against my instructions to contact me with the diagnosis before doing anything. I would've declined that "repair". Once again I heard the noise in the parking lot. Each time the dealer touches it, I notice things that weren't quite put together the same as when brought in. Still, as far as dealer work goes, they do a good job. But unless I'm doing something myself, (and sometimes even then,) I'm not perfectly satisfied.
 


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#9
Yeah I'm to the point that IDGAF. I'm going to just shift normally. I'm now beginning to hear a tid bit of clack releasing in 4th. I've been to the dealer twice about it and am done wasting my time. First time they couldn't reproduce the problem... which is believable. But I heard it the moment I started to leave the parking lot. The second time they replaced the axle shafts; and against my instructions to contact me with the diagnosis before doing anything. I would've declined that "repair". Once again I heard the noise in the parking lot. Each time the dealer touches it, I notice things that weren't quite put together the same as when brought in. Still, as far as dealer work goes, they do a good job. But unless I'm doing something myself, (and sometimes even then,) I'm not perfectly satisfied.
I wish mine were that imperceptible. Every gear change sounds like my old '71 BMW R75/5 clacking into gear. I just write it off as "racecar" experience.
 


Intuit

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#10
They have to get approval from Ford... and Ford is going to go with the cheapest "solution" before resolving to the later, of removing the engine to replace the (expensive) flywheel. THe clack is intermittent, but progressively more persistent. When it does occur, it can be head-turning loud on the clutch release into 2nd gear. (and this is at low speed, low RPM)
 




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