rattling noise during 1st gear

sean77693 · 10-01-2016, 11:25 PM

2009 370 z M6

Dont listen to anyone if they tell you that this noise is normal...if youre anything like me when it comes to my toys im exceptionally "OCD" shall we say about anything that feels or sounds like it could be a problem. That being said, ive looked into this noise because my car just recently started making it, but ive heard other cars throughout my life make the same noise, so it wouldnt be a manufacturer spec. problem. Then i YouTubed any videos i could find to see if i could hear a replication of the noise. After a few hours and some research, along with my auto tech history and knowledge i came to my own conclusion, which is....

Because the sound is only at low RPMs
always taking off from a slow or dead stop
goes away when the car is up to speed and rpms are up
and seems to only happen when the clutch is engaged (pedal NOT pressed)
i believe that the problem comes from and input shaft bearing or a pilot bearing, when these wear and there is play it will cause the clutch to engage with the pressure plate not quite exactly dead center this makes a harmonic vibration or a chatter noise that is amplified by the bell houseing of the transmission. When the Rpms rise the clutch disc spins faster causing centrifugal force to align the clutch and pressure plate and balance the shaft. Thus no more vibration, and no more noise. All that said the bearing isnt really going to cause any mechanical problems, at least initially however, if the wear becomes too excessive i suppose it could cause alignment issues in the transmission... but personally i cant stand the rattle so for peace of mind i just think ill replace all bearings, may as well they are cheap and if it needs to be taken apart for one might as well get ahead on preventative maint... ill follow up after the service to confirm or feel stupid and apologize..

NOT to be confused with a throwout bearing.....pilot/input bearing.

I could be wrong but from what ive seen, read, and experienced this is my theory.
https://youtu.be/nWWi74xKt8A

Rahul718 · 10-02-2016, 04:10 PM

Quote:

Originally Posted by sean77693

2009 370 z M6

Dont listen to anyone if they tell you that this noise is normal...if youre anything like me when it comes to my toys im exceptionally "OCD" shall we say about anything that feels or sounds like it could be a problem. That being said, ive looked into this noise because my car just recently started making it, but ive heard other cars throughout my life make the same noise, so it wouldnt be a manufacturer spec. problem. Then i YouTubed any videos i could find to see if i could hear a replication of the noise. After a few hours and some research, along with my auto tech history and knowledge i came to my own conclusion, which is....

Because the sound is only at low RPMs
always taking off from a slow or dead stop
goes away when the car is up to speed and rpms are up
and seems to only happen when the clutch is engaged (pedal NOT pressed)
i believe that the problem comes from and input shaft bearing or a pilot bearing, when these wear and there is play it will cause the clutch to engage with the pressure plate not quite exactly dead center this makes a harmonic vibration or a chatter noise that is amplified by the bell houseing of the transmission. When the Rpms rise the clutch disc spins faster causing centrifugal force to align the clutch and pressure plate and balance the shaft. Thus no more vibration, and no more noise. All that said the bearing isnt really going to cause any mechanical problems, at least initially however, if the wear becomes too excessive i suppose it could cause alignment issues in the transmission... but personally i cant stand the rattle so for peace of mind i just think ill replace all bearings, may as well they are cheap and if it needs to be taken apart for one might as well get ahead on preventative maint... ill follow up after the service to confirm or feel stupid and apologize..

NOT to be confused with a throwout bearing.....pilot/input bearing.

I could be wrong but from what ive seen, read, and experienced this is my theory.
https://youtu.be/nWWi74xKt8A

Nissan replaced the transmission on my 2014 Nismo last year for an unrelated reason. The old transmission made the same noise when taking off in 1st gear when the car was hot and the new transmission makes the same noise. So I'm not inclined to agree with you on this. I've learned to let go of any OCD regarding transmission noises. These are noisy transmissions but as long as they function fine, I've accepted it.

ShockWave · 02-25-2013, 03:50 PM

what can we do to fix?

ShockWave · 03-15-2013, 08:43 AM

UPDATE: I notice that I don't hear any rattling noise in the morning when the car is cool. any thoughts?

Sh0velMan · 03-15-2013, 12:20 PM

Quote:

Originally Posted by ShockWave

UPDATE: I notice that I don't hear any rattling noise in the morning when the car is cool. any thoughts?

Do you feel it in the pedal?

I used to feel it in the pedal when it was hot, not when it was cold.

Then my clutch master cylinder went out after the fluid boiled... replaced that, flushed with RBF600, no more rattle or pulsating pedal.

Take a pic of your clutch master cylinder with a camera, good light but not flash, so we can see the color/quality of the fluid.

ShockWave · 03-15-2013, 12:48 PM

what do u guys think?

ShockWave · 03-15-2013, 12:53 PM

how do i do a Fluid Flush? It don't look right. do u guys think i need to replace the clutch master cylinder? How many bottles of RBF600 do I need? What the best thing to do so this won't happen again? How much to flush if take to Nissan?

Sh0velMan · 03-15-2013, 02:54 PM

That definitely needs to be flushed.

No idea how much it will cost at dealer.

One pint should be sufficient.

ShockWave · 03-15-2013, 03:17 PM

thanks!!! what do you think cause the issues and how to keep it from happening again?

cheshirecat · 03-18-2013, 02:21 PM

You could always do what the vette guys do and use a turkey-baster type device to suck the crap out the reservoir and pour new stuff in. As you drive, it'll cycle and dilute. Keep checking periodically and do the same thing until it's clean.

Just a suggestion if you don't want to pay for a flush or get under the vehicle.

phohman · 03-18-2013, 02:31 PM

It will Gravity bleed just about on it's own. Crack the bleeder and maintain the fluid level until u see fresh fluid coming out the bottom. Very simple!

ShockWave · 03-18-2013, 10:38 PM

Quote:

Originally Posted by phohman

It will Gravity bleed just about on it's own. Crack the bleeder and maintain the fluid level until u see fresh fluid coming out the bottom. Very simple!

If I crack the bleeder how long will it take till I start seeing clean fluid coming out? Also will that damage the clutch if fluid is low? Any pics on where the bleed screw for the clutch is?

ShockWave · 03-18-2013, 10:35 PM

wish you guys told me this sooner. Just paid $180 to get it done. Update: The rattling noise went away and notices my temp don't pass 200. Before my temp was around 230 on DD.

ShockWave · 03-21-2013, 06:17 PM

how long does it take for the Fluid to start getting brown again? Mine is starting to get dirty again. Its a light brown color right now and I just got it flushed about a week ago.

ShockWave · 03-26-2013, 07:00 PM

Up date: I made a video of the "rattling noise" you can hear it at 0:16 - 0:17 ....thats the sound I've been hearing.

370z rattling noise - YouTube

10-01-2016, 11:25 PM	#1 (permalink)
sean77693 Base Member Join Date: Aug 2016 Location: saint george utah Posts: 3 Drives: 09 Nissan 370z M6 Rep Power: 10	rattling noise when taking off in 1st, almost sounds like exhaust rattle 2009 370 z M6 Dont listen to anyone if they tell you that this noise is normal...if youre anything like me when it comes to my toys im exceptionally "OCD" shall we say about anything that feels or sounds like it could be a problem. That being said, ive looked into this noise because my car just recently started making it, but ive heard other cars throughout my life make the same noise, so it wouldnt be a manufacturer spec. problem. Then i YouTubed any videos i could find to see if i could hear a replication of the noise. After a few hours and some research, along with my auto tech history and knowledge i came to my own conclusion, which is.... Because the sound is only at low RPMs always taking off from a slow or dead stop goes away when the car is up to speed and rpms are up and seems to only happen when the clutch is engaged (pedal NOT pressed) i believe that the problem comes from and input shaft bearing or a pilot bearing, when these wear and there is play it will cause the clutch to engage with the pressure plate not quite exactly dead center this makes a harmonic vibration or a chatter noise that is amplified by the bell houseing of the transmission. When the Rpms rise the clutch disc spins faster causing centrifugal force to align the clutch and pressure plate and balance the shaft. Thus no more vibration, and no more noise. All that said the bearing isnt really going to cause any mechanical problems, at least initially however, if the wear becomes too excessive i suppose it could cause alignment issues in the transmission... but personally i cant stand the rattle so for peace of mind i just think ill replace all bearings, may as well they are cheap and if it needs to be taken apart for one might as well get ahead on preventative maint... ill follow up after the service to confirm or feel stupid and apologize.. NOT to be confused with a throwout bearing.....pilot/input bearing. I could be wrong but from what ive seen, read, and experienced this is my theory. https://youtu.be/nWWi74xKt8A Last edited by sean77693; 10-01-2016 at 11:33 PM. Reason: added more

03-15-2013, 12:53 PM	#7 (permalink)
ShockWave Enthusiast Member Join Date: Dec 2011 Location: houston Posts: 303 Drives: 350z Rep Power: 15	how do i do a Fluid Flush? It don't look right. do u guys think i need to replace the clutch master cylinder? How many bottles of RBF600 do I need? What the best thing to do so this won't happen again? How much to flush if take to Nissan? Last edited by ShockWave; 03-15-2013 at 01:51 PM.

03-15-2013, 02:54 PM	#8 (permalink)
Sh0velMan A True Z Fanatic Join Date: Jan 2012 Location: Dallas/Ft.Worth Posts: 3,349 Drives: Noisily. Rep Power: 22	That definitely needs to be flushed. No idea how much it will cost at dealer. One pint should be sufficient. __________________ Buy My Car! \| Build Thread

03-18-2013, 02:31 PM	#11 (permalink)
phohman Base Member Join Date: Feb 2011 Location: Katy-Houston Tx. Age: 63 Posts: 124 Drives: 2012 370Z Nismo Rep Power: 16	It will Gravity bleed just about on it's own. Crack the bleeder and maintain the fluid level until u see fresh fluid coming out the bottom. Very simple! __________________ INGEN CAI BERK HFC Z1 SS BRAKE LINES ICHIBA 15mm SPACERS 25 ROW OIL COOLER Z1 ENGINE UNDERSHROUD COVER Z1 AKEBONO ROTORS QUAIFE DIFF w NISMO DIFF COVER WHITELINE BUSHINGS

03-18-2013, 10:35 PM	#13 (permalink)
ShockWave Enthusiast Member Join Date: Dec 2011 Location: houston Posts: 303 Drives: 350z Rep Power: 15	wish you guys told me this sooner. Just paid $180 to get it done. Update: The rattling noise went away and notices my temp don't pass 200. Before my temp was around 230 on DD. Last edited by ShockWave; 03-18-2013 at 10:55 PM.

02-25-2013, 03:50 PM	#3 (permalink)
ShockWave Enthusiast Member Join Date: Dec 2011 Location: houston Posts: 303 Drives: 350z Rep Power: 15	what can we do to fix?

03-15-2013, 08:43 AM	#4 (permalink)
ShockWave Enthusiast Member Join Date: Dec 2011 Location: houston Posts: 303 Drives: 350z Rep Power: 15	UPDATE: I notice that I don't hear any rattling noise in the morning when the car is cool. any thoughts?

03-15-2013, 03:17 PM	#9 (permalink)
ShockWave Enthusiast Member Join Date: Dec 2011 Location: houston Posts: 303 Drives: 350z Rep Power: 15	thanks!!! what do you think cause the issues and how to keep it from happening again?

03-18-2013, 02:21 PM	#10 (permalink)
cheshirecat A True Z Fanatic Join Date: Jan 2009 Location: Florida Posts: 1,428 Drives: N54 135i Rep Power: 294	You could always do what the vette guys do and use a turkey-baster type device to suck the crap out the reservoir and pour new stuff in. As you drive, it'll cycle and dilute. Keep checking periodically and do the same thing until it's clean. Just a suggestion if you don't want to pay for a flush or get under the vehicle.

03-21-2013, 06:17 PM	#14 (permalink)
ShockWave Enthusiast Member Join Date: Dec 2011 Location: houston Posts: 303 Drives: 350z Rep Power: 15	how long does it take for the Fluid to start getting brown again? Mine is starting to get dirty again. Its a light brown color right now and I just got it flushed about a week ago.

03-26-2013, 07:00 PM	#15 (permalink)
ShockWave Enthusiast Member Join Date: Dec 2011 Location: houston Posts: 303 Drives: 350z Rep Power: 15	Up date: I made a video of the "rattling noise" you can hear it at 0:16 - 0:17 ....thats the sound I've been hearing. 370z rattling noise - YouTube

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