[magic77]

So today car went into for interim oil change and few other bits.

While inspecting the car we noticed the rear subframes vibration damper to be badly loose.

The unit is mounted through the rear subframe direct into rear diff. Huge chuck of steel with a rubber grommet and then metal nut. The rubber bush has totally perished and the unit while tight to the car was rattling like something crazy.

Car is a 2014 plate with 23,000 miles on clock. :

Expected things as simple as this to last longer.

Item 7 in the link below

https://www.realoem.com/bmw/enUS/sho...31#33176856504

Seems nothing major but the way the rubber has come loose I woudl not trust the part to stay on the car any longer and hate to think the damage it coudl do do to the car or another vehicle if it came off.

[NanasBack]

Another potential recall safety issue?

[magic77]

I suspect not , takes someone to have major accident like the e90 fire recall before they do anything it seems. Joy of cars made to last only few years unlike before

[RobUK]

Yeah, you'd hope something like that would survive normal wear & tear a lot longer than 3½years. What's it going to cost to fix?

[NISFAN]

Originally Posted by RobUK

Yeah, you'd hope something like that would survive normal wear & tear a lot longer than 3½years. What's it going to cost to fix?

Nothing, take it off and throw it away like I did

[magic77]

Did yours also wear out. Its the vibrations that could be issue post removal especially at higher speeds.

Will find out tommorow how much the part is

[NISFAN]

No, but it's a 1.2kg weight that doesn't belong on the car. I have 2 or 3 of them in the garage

[ZHP076]

Originally Posted by NISFAN

No, but it's a 1.2kg weight that doesn't belong on the car. I have 2 or 3 of them in the garage

And the diff will cool faster without that hunk of thick rubber and steel insulating it. It would take an factory expert at NVH to tell it was missing.

[Mr Whippy]

Until you hit the perfect combo of oscillation and your diff cog wheels go crunch.

Chances are it’s not for nvh when pootling around, but in high slip conditions and the drivetrain is loading/unloading, and making sure the natural frequency is pushed to one unlikely to be reached.

[Sasquartch]

Originally Posted by Mr Whippy

Until you hit the perfect combo of oscillation and your diff cog wheels go crunch.

Chances are it’s not for nvh when pootling around, but in high slip conditions and the drivetrain is loading/unloading, and making sure the natural frequency is pushed to one unlikely to be reached.

I'd have to agree with this

No way BMW would fit a part that was unnecessary, for cost or weight reasons.

I'd make sure the correct part is refitted.

[NISFAN]

Originally Posted by Sasquartch

I'd have to agree with this

No way BMW would fit a part that was unnecessary, for cost or weight reasons.

I'd make sure the correct part is refitted.

Perhaps, but I've done over 100k miles now without it. Including fastest lap time for a diesel in the "howfast" event, so I don't think you could consider the car not pushed to the extremes.
I've not felt any kind of increased NVH or any other ill effects like worn out diff bearing or exploding gears.

[magic77]

The device is a 80hz rated so more likely its for idle speeds to reduce vibrations coming through the car. A bit like on the 320D on the exhaust on the e90 there use to be a huge rubber version similar to this to reduce the exhaust shake on idle.

I certainly noticed a new noise with it off. Was so tempted to reach over on the production line in munic and borrow one during recent visist (if only)