[arkangyl]

I didn't see much on this in searching, issues seemed more about some vibration from 50-85

My 2014 F30 335 xDrive is starting to vibrate noticeably, at idle it causes rattles in the cabin, and it doesn't really go away until 70 and above (still there, but far more muted)

When I'm stopped, if I flip from drive to neutral it goes away 100%

There's also a sound under 1500 rpm, reminds me of a 6-puck race clutch I used to have in a built STI

I'm thinking either clutch or transmission bushings, but curious if anyone else has had similar issues?

I noticed this a bit over the winter, with dedicated winter wheels & tires, but that felt more like a minor balance thing (vibration between 60 and 85 - seems to be a thing?). It got a bit better when the summers came back on a few weeks ago, but has been noticeably worse the last few days as I've sat in traffic more

2014 335 xDrive sedan M-Sport
57,000 miles
8AT (not the 'sport' option, no paddles)
OEM Continental summer runflats, about 8k miles on them
just had service last week (60k maintenance + brake pads)

(yes, I've reached out to my SA as it's under CPO warranty - but I'm all for trying to figure out what it could be just in case)

thanks!

[Billfitz]

Rattling the cabin at idle makes me suspect motor mounts.

[kern417]

Try crusing at higher rpm (3k+) when you're driving below 70 to see if it's really speed dependent or perhaps rpm dependent. If it goes away with higher rpm then i'd bet engine mounts too.

[arkangyl]

Thanks for the feedback - it seems a bit better >3k rpm

I'm a little surprised it'd be motor mounts if it's OK with the engine running but the transmission disengaged

[COKen]

Originally Posted by arkangyl

Thanks for the feedback - it seems a bit better >3k rpm

I'm a little surprised it'd be motor mounts if it's OK with the engine running but the transmission disengaged

I don't know, but I would guess that with the transmission engaged, then the engine is under load and with the transmission disengaged it is not. So I'm not surprised you would feel the vibration when the transmission is disengaged.

This would be the similar to feeling it while accelerating, but not at speed. The engine is under load while accelerating, but not so much while at speed and not accelerating.

[arkangyl]

To update, on Saturday I drove the car to a local BMW dealership (on the phone they said they could a day-of diagnostics, when I got there they had no idea what I was talking about...) and the vibration was pretty bad. I jacked the car up to look around after (front, driver side) but didn't find anything. I did drive the car pretty hard back from the dealer because of frustration :-)

Appointment was made with BMW in Boston (excellent experiences so far!) to inspect but on the drive in the car was fine - minor vibrations but about inline with the quality of roads in MA... They took a look and didn't find anything wrong with it - checked engine & transmission mounts, etc.

So... besides wait & see I'm wondering if the clutch in the 8AT got a bit glazed from weeks of rush hour crawling, and a day of hard shifting cleaned it up? that's the only theory I've got right now

[kern417]

Originally Posted by arkangyl

To update, on Saturday I drove the car to a local BMW dealership (on the phone they said they could a day-of diagnostics, when I got there they had no idea what I was talking about...) and the vibration was pretty bad. I jacked the car up to look around after (front, driver side) but didn't find anything. I did drive the car pretty hard back from the dealer because of frustration :-)

Appointment was made with BMW in Boston (excellent experiences so far!) to inspect but on the drive in the car was fine - minor vibrations but about inline with the quality of roads in MA... They took a look and didn't find anything wrong with it - checked engine & transmission mounts, etc.

So... besides wait & see I'm wondering if the clutch in the 8AT got a bit glazed from weeks of rush hour crawling, and a day of hard shifting cleaned it up? that's the only theory I've got right now

It could be anything before the driveshaft if it's RPM dependent. Another thing you can do when it's bad is try to turn the A/C on and off to see if the additional load makes a difference at idle.

[Sea-Tac]

If it smoothes out at speed and you only notice it at start up, I think it might be motor mount left side engine rear. Someone in another post in an X3 forum said that was fairly common.

[arkangyl]

that would definitely make sense

it's been fine at idle lately, and good over 60 mph, but at low speeds it feels like the whole car is rocking from side to side, slowly smoothing out as speed increases

[arkangyl]

heard back from the dealer - TWO bent wheels (front passenger & rear driver), the front was bent much worse than the rear

I'm a little surprised given the symptoms, but it does make sense...

[kingmonkey8]

Originally Posted by arkangyl

heard back from the dealer - TWO bent wheels (front passenger & rear driver), the front was bent much worse than the rear

I'm a little surprised given the symptoms, but it does make sense...

So did you change the wheels and was the vibration fixed?
When you say vibration was there any noise like a rumbling or booming noise?

[kingmonkey8]

Originally Posted by arkangyl

heard back from the dealer - TWO bent wheels (front passenger & rear driver), the front was bent much worse than the rear

I'm a little surprised given the symptoms, but it does make sense...

So did you change the wheels and was the vibration fixed?
When you say vibration was there any noise like a rumbling or boomy noise?