Gear Box noise 6MT

[Imo135]

Hi

I am not sure if this was discussed before (could not find anything)but maybe I can get some answers still....

On a N54 6MT, when switching off the car the gearbox rattles (intermittently), bit a a metally sound, something like a bolt in a metal bucket.

Also, intermittently when standing at a robot and no gear engaged there is another rattly sound, something like a loose bolt rattling, when I engage clutch (no gear) it goes away, this leads me to believe its the release bearing. The car has under 15000 miles and is a 2008/2009.

The dealers said its due to all their performance manual cars using a gearbox with a floating release bearing and this is the character of the gearbox and is the case with all perf cars (m cars as well). Nothing can be done about it according to them.

Does anyone know what this is and does anyone have the same problem? Is the explanation provided by BMW correct? The car is still under warranty..

[Gumball]

Sound is normal - dont worry about it!

[Imo135]

Originally Posted by Gumball

Sound is normal - dont worry about it!

THANK U for the reply!

[sardius]

Mine is N55 and rattles when switching off the engine with foot off the clutch. Normal.

[ErvGotti]

Yeah even though I hate it, it is supposedly normal. Something about the dual mass flywheel. Push the clutch in while shutting the car off and it will get rid of the rattling.

[drewh130]

I always attributed this to "hot spots" spots on the clutch. I actually had my clutch and flywheel replaced under warranty recently due to the chatter when taking off in 1st gear. But it started doing it again almost immediatley. Does anyone know if this chatter is normal?

[tracer bullet]

Originally Posted by Imo135

when I engage clutch (no gear) it goes away, this leads me to believe its the release bearing.

I believe that the release bearing (aka throw-out bearing) only spins when the clutch pedal is pushed in. If you are not in gear and your foot is off the pedal, it is not spinning. If that's true (pretty sure it is) then that's not the source of your noise.

[07'335iAlpine]

This rattling sound your hearing isn't at all normal. although there is a slight sound similar to this that is NORMAL. I had this same issue recently (like a week ago). i have owned a AT transmission 335i and it made that Normal sound you and every other post'er regarded as normal and it is. But only to an extent, i just got my '10 135i AW/FR and it had that noise but alot more pronounced as you explained bolts in a bucket being rattled. it got worse and would occassionally start to sound as if it was engine knock, it got to the point where it would do it on cold starts and with the gearbox in nuetral....it sounded very bad. then i noticed that on shut off you could hear the exact sound breifly and it did this everytime i shut it off. so i then decided to take it in as i could easily duplicate this in front of the service advisor. As we all KNOW they LOVE to DISREGARD alot of things with these engines as NORMAL and send us on our way. Anyhow, I duplicated it for him and they said they would check it right away.....i even waited 2 hours at dealership while they checked cause i hadn't set an appointment up. i had just took it in. He came back and said there was definately an issue and that they were going to do a Flywheel/Clutch combo replacement. I just picked up my car about 2 days ago. and PROBLEM HAS BEEN SOLVED. that rattling sound is gone and it drives great.slight rattle on shut off is very vague now, no more bolts in a bucket....... It is covered underwarranty by the way so i had to pay nothing. GOOD LUCK to you. Hope this helps. sorry for the long write-up.

Jacob

[sardius]

Originally Posted by drewh130

I always attributed this to "hot spots" spots on the clutch. I actually had my clutch and flywheel replaced under warranty recently due to the chatter when taking off in 1st gear. But it started doing it again almost immediatley. Does anyone know if this chatter is normal?

When you are taking off in the 1st gear, do you feel a little vibration under your butt, almost coming from the rear axle (not sure exactly from where) but the car vibrates a little and briefly? When I give a little more gas obviously the chatter/vibration is not there, but I don't want to give unnecessary revs everytime when I take off.

[drewh130]

Originally Posted by sardius

When you are taking off in the 1st gear, do you feel a little vibration under your butt, almost coming from the rear axle (not sure exactly from where) but the car vibrates a little and briefly? When I give a little more gas obviously the chatter/vibration is not there, but I don't want to give unnecessary revs everytime when I take off.

yes this is exactly what I'm experiencing...

[Imo135]

Originally Posted by 07'335iAlpine

This rattling sound your hearing isn't at all normal. although there is a slight sound similar to this that is NORMAL. I had this same issue recently (like a week ago). i have owned a AT transmission 335i and it made that Normal sound you and every other post'er regarded as normal and it is. But only to an extent, i just got my '10 135i AW/FR and it had that noise but alot more pronounced as you explained bolts in a bucket being rattled. it got worse and would occassionally start to sound as if it was engine knock, it got to the point where it would do it on cold starts and with the gearbox in nuetral....it sounded very bad. then i noticed that on shut off you could hear the exact sound breifly and it did this everytime i shut it off. so i then decided to take it in as i could easily duplicate this in front of the service advisor. As we all KNOW they LOVE to DISREGARD alot of things with these engines as NORMAL and send us on our way. Anyhow, I duplicated it for him and they said they would check it right away.....i even waited 2 hours at dealership while they checked cause i hadn't set an appointment up. i had just took it in. He came back and said there was definately an issue and that they were going to do a Flywheel/Clutch combo replacement. I just picked up my car about 2 days ago. and PROBLEM HAS BEEN SOLVED. that rattling sound is gone and it drives great.slight rattle on shut off is very vague now, no more bolts in a bucket....... It is covered underwarranty by the way so i had to pay nothing. GOOD LUCK to you. Hope this helps. sorry for the long write-up.

Jacob

Thanks for this write up Jacob. I will take it to the dealer, hopefully I can pressurise them to sort it out.