Any 6MT folks noticing engine bay / rear diff noises?

[bdoooh]

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I've seen threads on various DCT folks hearing some grinding in the diff but I'm hearing 2 different noises that I think I'm going to mention when I take it in for my 1200mi service here in a week..

If I'm in 5th gear @ 35mph or any other gear at a lower RPM <1500.. When I get on the throttle I'll get a click click sound in the rear diff it sounds like. Every time I let off and get back on, it clicks. Like I can hear it over music, not loud music but nonetheless it's not something you have to really listen for.

2nd sound. If I'm at a lower RPM such as clutch idle.. And let in the clutch, I'll get a rattle in the engine bay. Or like if I'm navigating a parking lot in 1st gear and push in the clutch, I'll get the rattle. The closest thing I would compare it to is possible wastegate rattle or when you throw a rod in a car type of rattle.

I'll have to show the tech to see if they feel it's normal when I take it in.

[AMPowerJ]

The second sound is probably due to the lightweight flywheel and it's probably normal. Not sure about the first one ...

[IMrMark]

I'll have to try both of these scenarios sometime today if possible and report back. I don't remember anything out of the ordinary, but worth trying to duplicate to see.

[bdoooh]

Originally Posted by IMrMark

I'll have to try both of these scenarios sometime today if possible and report back. I don't remember anything out of the ordinary, but worth trying to duplicate to see.

Thank you! Let us know!

[dhoggm3]

Does the clutch sound with the clutch fully to the floor, or when it's fully released - with your foot off the clutch? If it's the latter, it's most likely the LTW flywheel. If it's the former, then IDK.

[JoeFromPA]

Remember too that some cars have different levels of tolerances that result in driveline lash (the noise described sounds like driveline lash to me).

[IMrMark]

I wasn't able to duplicate these noises under similar.. Sorry. That being said, my ears might just not be that good.. Think all was clear on my end tho. I did end up hearing the buzzing noise everyone else was talking about with the seat lights

[karussell]

gt3 rs is a heavy smoker when it starts up...like batmobile smokescreen levels and 3/4 times when you turn the key it buzzes like a chain saw. it sounds like a diesel at idle. you hear every pebble bounce off the fenders thrown off by the semislicks. the interior creeks from the cage rubbing it. ac hums. you couldn't even talk on the bt phone at speeds over 3k rpm which was pretty much whenever not stationary. it was glorious.

the m4 is too quiet still for me. i should rip out all the sound deadening. i love hearing it hiss, roar, and burp as it angrily accelerates or on throttle lift. congratulations you bought a sports car. it makes noises. 5th gear at 35mph is the problem. complain why it always wants to shed its tires instead. actually thats a bonus too.

seriously there are a billion sensors in the car. unless those throw a warning or you feel the clutch slipping then probably normal. the more complaints fielded over minor shit the more likely we get even more crap that isolates us from the car.

[bdoooh]

Originally Posted by dhoggm3

Does the clutch sound with the clutch fully to the floor, or when it's fully released - with your foot off the clutch? If it's the latter, it's most likely the LTW flywheel. If it's the former, then IDK.

It happens right when the engine is fully disconnected from the transmission quickly so when the clutch is to the floor.

[bdoooh]

Originally Posted by karussell

gt3 rs is a heavy smoker when it starts up...like batmobile smokescreen levels and 3/4 times when you turn the key it buzzes like a chain saw. it sounds like a diesel at idle. you hear every pebble bounce off the fenders thrown off by the semislicks. the interior creeks from the cage rubbing it. ac hums. you couldn't even talk on the bt phone at speeds over 3k rpm which was pretty much whenever not stationary. it was glorious.

the m4 is too quiet still for me. i should rip out all the sound deadening. i love hearing it hiss, roar, and burp as it angrily accelerates or on throttle lift. congratulations you bought a sports car. it makes noises. 5th gear at 35mph is the problem. complain why it always wants to shed its tires instead. actually thats a bonus too.

seriously there are a billion sensors in the car. unless those throw a warning or you feel the clutch slipping then probably normal. the more complaints fielded over minor shit the more likely we get even more crap that isolates us from the car.

Well I'm going to the track in a month or so.. and I don't want my diff or something weird to go out and fail on me in the middle of a track day and I'm out that money for the day.... Otherwise I really don't care.. it's under warranty, I'd let it fail on the street.

[RickMonet]

Originally Posted by bdoooh

Well I'm going to the track in a month or so.. and I don't want my diff or something weird to go out and fail on me in the middle of a track day and I'm out that money for the day.... Otherwise I really don't care.. it's under warranty, I'd let it fail on the street.

Any chance you can record the noise(s) and post?

[Reid]

Originally Posted by karussell

the more complaints fielded over minor shit the more likely we get even more crap that isolates us from the car.

[04RC51]

Well, guess the 6MT people have to throw away their cars too now. Glad I didn't get a 6MT.

[Never Convicted]

It's the Ghost of Transmissions Past.

[bdoooh]

Originally Posted by RickMonet

Any chance you can record the noise(s) and post?

I'll try this Sunday or Monday. Out of town until then. Poor M had to sit for a week without getting driven.

[tibookM3]

Does the manual still say something like "may hear mechanical noise, this is normal" for most of the drivetrain descriptions like it did on my E92? Because I'm almost positive it is supposed to be making these noises :-)

Remember it's not a GT no matter how big and refined it continues to get!

[AreOut]

equipment needed to solve DCT problems



equipment needed to solve MT problems

[igom3]

Originally Posted by bdoooh

I've seen threads on various DCT folks hearing some grinding in the diff but I'm hearing 2 different noises that I think I'm going to mention when I take it in for my 1200mi service here in a week..

If I'm in 5th gear @ 35mph or any other gear at a lower RPM <1500.. When I get on the throttle I'll get a click click sound in the rear diff it sounds like. Every time I let off and get back on, it clicks. Like I can hear it over music, not loud music but nonetheless it's not something you have to really listen for.

2nd sound. If I'm at a lower RPM such as clutch idle.. And let in the clutch, I'll get a rattle in the engine bay. Or like if I'm navigating a parking lot in 1st gear and push in the clutch, I'll get the rattle. The closest thing I would compare it to is possible wastegate rattle or when you throw a rod in a car type of rattle.

I'll have to show the tech to see if they feel it's normal when I take it in.

35mph in 5th gear? no wonder why you hear noises

[bdoooh]

Okay smart guy what rpm do you cruise at 35mph in??

..I prefer under 2...

[Powaup]

I hear no such noise in my car maybe you got a pebble in your diff?

[stressdoc]

The LSD is engaged and disengaged in part electronically. There is a notice/bulletin somewhere about clunks and clicks from the diff that are 'normal' and not a sign of malfunction.

[Oakleyguy]

Originally Posted by bdoooh

I've seen threads on various DCT folks hearing some grinding in the diff but I'm hearing 2 different noises that I think I'm going to mention when I take it in for my 1200mi service here in a week..

If I'm in 5th gear @ 35mph or any other gear at a lower RPM <1500.. When I get on the throttle I'll get a click click sound in the rear diff it sounds like. Every time I let off and get back on, it clicks. Like I can hear it over music, not loud music but nonetheless it's not something you have to really listen for.

2nd sound. If I'm at a lower RPM such as clutch idle.. And let in the clutch, I'll get a rattle in the engine bay. Or like if I'm navigating a parking lot in 1st gear and push in the clutch, I'll get the rattle. The closest thing I would compare it to is possible wastegate rattle or when you throw a rod in a car type of rattle.

I'll have to show the tech to see if they feel it's normal when I take it in.

1st sound: Yes, I experienced that once in a while. I believe that it's just drivetrain noise due to the lack of subframe bushings. It's like you're loading and unloading the drivetrain. Basically you're hearing the effect of lashing in the driveline.

2nd sound: Likely due to the Twin Plate clutch. They tend to chatter when the clutch is depressed. The flywheel wouldn't make the noise, but because it's a lightened unit, it won't dampen the noise as well.