Transmission rattling noise

lantyem · 02-05-2019, 10:45 PM

Hi,
I've had many problems with this transmission now. I followed this guide (https://www.e90post.com/forums/showthread.php?t=1193573) when I had transmission codes for bad shifts 4-3 and 5-4. That was maybe a month ago and since then, it has developed a rattling noise when in park or neutral. Every now and then it also won't go in reverse until I turn the car off. It hasn't thrown any codes relating to this (yet).
I've seen similar thread questions for the 6MT, but they're not relevant to my issue.

I took a video tonight of the sound (nothing but sound and the ground in the video):

slinkygn · 02-15-2019, 04:52 PM

Given that that could probably be a bunch of things and I'm barely a shadetree mechanic at best, I will say that I had those same symptoms shortly before my car stopped engaging in reverse altogether, and shortly after struggled in the forward gears too to the point where it was basically undrivable. The culprit ended up being the main valve body seal. If you look at the bottom of that post you linked to, you'll see two photos that seem unrelated to his instructions for swapping out solenoids -- the photo on the left is the seal I'm talking about. It's actually two seals with a plastic retainer holding the two, and the plastic had a huge crack on one side. Replaced the thing, reset adaptations and the tranny is better than I can ever remember it.

lantyem · 02-15-2019, 06:11 PM

Thanks for your reply.

After some reading I had come to believe two likely reasons were the mechatronic adapter (the part you mention) or a faulty torque converter.
I finally got a code yesterday on INPA, 4F82, which some people suggest also could be the rubber piece.
I ordered one from FCPEuro and will try that when it arrives (a $13 part)

lantyem · 03-04-2019, 11:46 PM

Quote:

Originally Posted by slinkygn

Given that that could probably be a bunch of things and I'm barely a shadetree mechanic at best, I will say that I had those same symptoms shortly before my car stopped engaging in reverse altogether, and shortly after struggled in the forward gears too to the point where it was basically undrivable. The culprit ended up being the main valve body seal. If you look at the bottom of that post you linked to, you'll see two photos that seem unrelated to his instructions for swapping out solenoids -- the photo on the left is the seal I'm talking about. It's actually two seals with a plastic retainer holding the two, and the plastic had a huge crack on one side. Replaced the thing, reset adaptations and the tranny is better than I can ever remember it.

Finally got the time to change the mechatronic adapter (ZF 24347588724.) Noise is gone and code hasn't come back. Here's the piece I changed out: https://www.imgur.com/a/wqC7oEa (can't get the [IMG] embedding to work..)

slinkygn · 03-07-2019, 04:34 AM

Yup, that was my problem too. Though in mine, instead of the rubber gasket breaking like it looks like yours did, I had a big crack in the plastic housing instead. I would think the gasket is the more common point of failure; no idea how the plastic cracked on mine... which reminds me, I should really check my transmission mounts soon.

lantyem · 04-20-2019, 07:08 PM

I've had some issues reappear, though this happened after the engine and transmission overheated. I had some noise again, thought much less noticeable than it used to be... but now the transmission would shift to the next gear (say, second to third) very late (car maybe at 3-3.5k rpm) and cause an abrupt jump, tires squealing, etc.
I took it apart again and found that the mechatronic adapter had ripped in the same spot and also noticed a lot of metallic parts on the pan.

Is the transmission done? =\

Boland01 · 04-21-2019, 08:17 AM

Quote:

Originally Posted by slinkygn

Given that that could probably be a bunch of things and I'm barely a shadetree mechanic at best, I will say that I had those same symptoms shortly before my car stopped engaging in reverse altogether, and shortly after struggled in the forward gears too to the point where it was basically undrivable. The culprit ended up being the main valve body seal. If you look at the bottom of that post you linked to, you'll see two photos that seem unrelated to his instructions for swapping out solenoids -- the photo on the left is the seal I'm talking about. It's actually two seals with a plastic retainer holding the two, and the plastic had a huge crack on one side. Replaced the thing, reset adaptations and the tranny is better than I can ever remember it.

Had the EXACT same issue on our 335i. Bad 4-5 shifts then just would go into neutral. When I pulled then pan and solenoid body I saw the plastic transmission seal had split. After replacing the car shifts like new again. Have 95K on ours.

Glene · 11-22-2020, 04:33 PM

does it sound like a metallic rattling noise? My car makes the same sound but I couldn't figure out where it's coming from. The noise seems to go away if I place in reverse. Coincidently that I recently changed the transmission fluid, the sound started after that. The trans shifts great, but the sound is getting louder. When in park, it makes like a metallic rattling sound. When you in drive, it sounds like a fan rubbing something. Place it in reverse, sound goes away.

30FF_ · 08-17-2021, 12:19 AM

Quote:

Originally Posted by Glene

does it sound like a metallic rattling noise? My car makes the same sound but I couldn't figure out where it's coming from. The noise seems to go away if I place in reverse. Coincidently that I recently changed the transmission fluid, the sound started after that. The trans shifts great, but the sound is getting louder. When in park, it makes like a metallic rattling sound. When you in drive, it sounds like a fan rubbing something. Place it in reverse, sound goes away.

Did you ever fix your problem I just did a full service on my vehicle today and finished everything up with new mech seal and sleeves and have the exact same metal noise and car shifts by itself and goes into nuetral don't know if I should just keep putting in more fluid because it isn't full yet and I stopped putting fluid in once noise started or should I just pull the pan and check the mech seal

MellowAmbitions · 02-05-2025, 01:21 PM

Quote:

Originally Posted by 30FF_

Did you ever fix your problem I just did a full service on my vehicle today and finished everything up with new mech seal and sleeves and have the exact same metal noise and car shifts by itself and goes into nuetral don't know if I should just keep putting in more fluid because it isn't full yet and I stopped putting fluid in once noise started or should I just pull the pan and check the mech seal

Did you ever figure it out?

02-05-2019, 10:45 PM	#1
lantyem New Member 2 Rep 12 Posts Drives: 2007 335i Join Date: Feb 2019 Location: FL iTrader: (0)	Transmission rattling noise Hi, I've had many problems with this transmission now. I followed this guide (https://www.e90post.com/forums/showthread.php?t=1193573) when I had transmission codes for bad shifts 4-3 and 5-4. That was maybe a month ago and since then, it has developed a rattling noise when in park or neutral. Every now and then it also won't go in reverse until I turn the car off. It hasn't thrown any codes relating to this (yet). I've seen similar thread questions for the 6MT, but they're not relevant to my issue. I took a video tonight of the sound (nothing but sound and the ground in the video):
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02-15-2019, 04:52 PM	#2
slinkygn Private 17 Rep 60 Posts Drives: 2007 335i M-Sport Join Date: Aug 2015 Location: TX, US iTrader: (0)	Given that that could probably be a bunch of things and I'm barely a shadetree mechanic at best, I will say that I had those same symptoms shortly before my car stopped engaging in reverse altogether, and shortly after struggled in the forward gears too to the point where it was basically undrivable. The culprit ended up being the main valve body seal. If you look at the bottom of that post you linked to, you'll see two photos that seem unrelated to his instructions for swapping out solenoids -- the photo on the left is the seal I'm talking about. It's actually two seals with a plastic retainer holding the two, and the plastic had a huge crack on one side. Replaced the thing, reset adaptations and the tranny is better than I can ever remember it.
	Appreciate 0 Quote

02-15-2019, 06:11 PM	#3
lantyem New Member 2 Rep 12 Posts Drives: 2007 335i Join Date: Feb 2019 Location: FL iTrader: (0)	Thanks for your reply. After some reading I had come to believe two likely reasons were the mechatronic adapter (the part you mention) or a faulty torque converter. I finally got a code yesterday on INPA, 4F82, which some people suggest also could be the rubber piece. I ordered one from FCPEuro and will try that when it arrives (a $13 part)
	Appreciate 0 Quote

03-07-2019, 04:34 AM	#5
slinkygn Private 17 Rep 60 Posts Drives: 2007 335i M-Sport Join Date: Aug 2015 Location: TX, US iTrader: (0)	Yup, that was my problem too. Though in mine, instead of the rubber gasket breaking like it looks like yours did, I had a big crack in the plastic housing instead. I would think the gasket is the more common point of failure; no idea how the plastic cracked on mine... which reminds me, I should really check my transmission mounts soon.
	Appreciate 0 Quote

04-20-2019, 07:08 PM	#6
lantyem New Member 2 Rep 12 Posts Drives: 2007 335i Join Date: Feb 2019 Location: FL iTrader: (0)	I've had some issues reappear, though this happened after the engine and transmission overheated. I had some noise again, thought much less noticeable than it used to be... but now the transmission would shift to the next gear (say, second to third) very late (car maybe at 3-3.5k rpm) and cause an abrupt jump, tires squealing, etc. I took it apart again and found that the mechatronic adapter had ripped in the same spot and also noticed a lot of metallic parts on the pan. Is the transmission done? =\ Attached Images
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11-22-2020, 04:33 PM	#8
Glene First Lieutenant 71 Rep 323 Posts Drives: 335is Join Date: Dec 2018 Location: Michigan iTrader: (0)	does it sound like a metallic rattling noise? My car makes the same sound but I couldn't figure out where it's coming from. The noise seems to go away if I place in reverse. Coincidently that I recently changed the transmission fluid, the sound started after that. The trans shifts great, but the sound is getting louder. When in park, it makes like a metallic rattling sound. When you in drive, it sounds like a fan rubbing something. Place it in reverse, sound goes away.
	Appreciate 0 Quote