[blackrabbit]

So I have this very annoying, but intermittent knock on my F30. It sounds like its at the rear end, but cant replicate it when I try to locate it.

It seems most common at slow speeds, ie in car parks etc. I have tried bumps and dips on the road, but this does not trigger it. It almost sounds like something banging in the boot (yes I have made sure its empty)

I notice some people with adaptive suspension had problems, but I just have M sport standard. Any tips or pointers would be appreciated.

[Theone88]

Originally Posted by blackrabbit

So I have this very annoying, but intermittent knock on my F30. It sounds like its at the rear end, but cant replicate it when I try to locate it.

It seems most common at slow speeds, ie in car parks etc. I have tried bumps and dips on the road, but this does not trigger it. It almost sounds like something banging in the boot (yes I have made sure its empty)

I notice some people with adaptive suspension had problems, but I just have M sport standard. Any tips or pointers would be appreciated.

Sure there's nothing in the compartment underneath the floor of the boot? Just checking cause I thought I lost something not long ago, blamed the Mrs for taking it and found it in there! ?

[ioannisG]

I'm having a similar sound from the back of the car. I've pinpointed it to the driver side back seat creaking when the body twists over speed bumps with one wheel on them.

It also happens when going in my drive. Haven't gone to BMW to ask for a fix yet but it's on the list...

[ronime]

I get a faint knocking sound now and again.

Is the plastic tray behind the near side wheel arch properly located in the carpet?

Is the bumper skin rattling against the mounting bracket?

[ajfoggy]

Try a little drive with the boot open to rule out the boot catch.

[a803sgo]

Originally Posted by ioannisG

I'm having a similar sound from the back of the car. I've pinpointed it to the driver side back seat creaking when the body twists over speed bumps with one wheel on them.

It also happens when going in my drive. Haven't gone to BMW to ask for a fix yet but it's on the list...

Same as mine, thought it was rear drop links at first.

[ioannisG]

Originally Posted by a803sgo

Same as mine, thought it was rear drop links at first.

So how did you get it fixed? Loathing to take the car to the dealers tbh

[KS_340i]

I have something similar in mine, clunk/knocking sound coming from the back only over certain bumps, sometimes on flat, and very inconsistent.

I had service manager sitting in the boot for a drive a week or so back and he heard it but could not figure out what it was, but seemed to be coming from boot locking mechanism. Booked in for next week where they will strip away some of the trim and drive around and see if they can replicate it.

[blackrabbit]

Thanks for the tips. I have done some investigating in the boot and think it may be the emergency triangle sliding in the boot lid, or the actual lift up panel in the boot. I have padded both and will see how it goes.

On a side note I realised my rear seats dont drop! How stupid is that?

[Daftasabrush]

Originally Posted by blackrabbit

On a side note I realised my rear seats dont drop! How stupid is that?

Optional extra I'm afraid!

[blackrabbit]

I never checked when I bought it......assumption and all that. Annoyingly it makes my 4 door F30 less practical than my totally impractical 2 door E92 with split drop seats!

[mikeysix]

Originally Posted by blackrabbit

Thanks for the tips. I have done some investigating in the boot and think it may be the emergency triangle sliding in the boot lid, or the actual lift up panel in the boot. I have padded both and will see how it goes.

On a side note I realised my rear seats dont drop! How stupid is that?

Hi mate, did you resolve this knocking? Sounds exactly the same as what I can hear

[blackrabbit]

No.... the knock is still there. I have turned the radio up until i have time too look again.

[TopperXP]

Had exactly the same on mine when i got it , was doing my head in . Mine was the back seat where it clips into 2 holders that are spring loaded , you should be able to replicate the noise by pulling back and forwards on the rear headrests.

I cured mine by spraying a load of spray grease into the clips and down the back of the seat using the straw on the spray can , i have not heard it since .

I thought it was a broken spring at first it was that bad !

[mikeysix]

Originally Posted by TopperXP

Had exactly the same on mine when i got it , was doing my head in . Mine was the back seat where it clips into 2 holders that are spring loaded , you should be able to replicate the noise by pulling back and forwards on the rear headrests.

I cured mine by spraying a load of spray grease into the clips and down the back of the seat using the straw on the spray can , i have not heard it since .

I thought it was a broken spring at first it was that bad !

Sound mate, I will have a look at that tonight! 👍🏻👍🏻

[JRF30]

Any solutions?