Not joined yet? Register for free and enjoy features such as alerts, private messaging and viewing latest posts and topics.

Front suspension rattly knocking noise over bumps

Discuss problems you have had or are having with your Z4
Dean'o
Member
Member
Posts: 166
Joined: Sun Jan 02, 2022 10:38 am
Location: Nottingham

Front suspension rattly knocking noise over bumps

Post by Dean'o » Sun May 22, 2022 2:16 pm

Can't hear rattle sound when driving. But knocking sound.

User avatar
kis
Lifer
Lifer
Posts: 4545
Joined: Wed Jul 20, 2016 2:33 pm
Location: Surrey / West Sussex Boarder

Front suspension rattly knocking noise over bumps

Post by kis » Sun May 22, 2022 6:06 pm

The dust shield is pretty notorious for corroding away. Most of our cars are between 15 and 20 years old...
Just unsure whether it would rattle. It should be more a scraping sound. But one to check out before you look at forking out any more money?
My E85 Z4 3.0i SMG

BMW Family History (past and present):
1 Series - E87
3 Series - E46 Coupe, E46 M3, E90 (x3)
4 Series - F36, F82 M4
5 Series - E34 (x2), E39
7 Series - E32
X5 - E53, E70
X6 - E71

Dean'o
Member
Member
Posts: 166
Joined: Sun Jan 02, 2022 10:38 am
Location: Nottingham

Front suspension rattly knocking noise over bumps

Post by Dean'o » Sun May 22, 2022 6:19 pm

Dust shield looks ok, it definitely at the wheel on both sides. Can't hear it when driving. Just the knocking sound. Going to sort sway bar bushes out next week. Have renewed control arms drop links and strut mounts. I have a got a wheel wobble through steering wheel, whether the two are linked not sure, been told front wheels are slightly buckled,

User avatar
kis
Lifer
Lifer
Posts: 4545
Joined: Wed Jul 20, 2016 2:33 pm
Location: Surrey / West Sussex Boarder

Front suspension rattly knocking noise over bumps

Post by kis » Mon May 23, 2022 2:22 pm

I'm doubtful that you would get that from a sway bar? Bushes are cheap. And should be easy to install. So you will know shortly.

If that fails, what about the wheel bearing?
My E85 Z4 3.0i SMG

BMW Family History (past and present):
1 Series - E87
3 Series - E46 Coupe, E46 M3, E90 (x3)
4 Series - F36, F82 M4
5 Series - E34 (x2), E39
7 Series - E32
X5 - E53, E70
X6 - E71

HGoward
Member
Member
Posts: 95
Joined: Sun Jan 03, 2021 3:47 pm
Location: Loughborough

Front suspension rattly knocking noise over bumps

Post by HGoward » Mon May 23, 2022 2:25 pm

If it was a constant rattle whilst driving, I would say top mounts. But I'm unsure if you can't hear it when driving.
Sapphire Black E86 LN56 ZKJ Purchased Jan 2021 - Sold June 2022
Bilstein B12 Pro Kit
Eisenmann Quad Exhaust
BMW Z4M Rear Bumper

User avatar
bigwinn
Lifer
Lifer
Posts: 4625
Joined: Wed Jul 08, 2020 7:13 pm
Location: Lincoln UK
Contact:

Front suspension rattly knocking noise over bumps

Post by bigwinn » Mon May 23, 2022 2:35 pm

can you see any obvious cracking on top mount rubber?
If the forum helped you, why not help the forum back. Thats the Z4 way! :thumbsup:

Image


EWS Delete PM me
Coding- airbags etc PM me

Dean'o
Member
Member
Posts: 166
Joined: Sun Jan 02, 2022 10:38 am
Location: Nottingham

Front suspension rattly knocking noise over bumps

Post by Dean'o » Mon May 23, 2022 2:40 pm

New top mounts new control arms new drop links. Unless wheels not balanced properly or buckled

Dean'o
Member
Member
Posts: 166
Joined: Sun Jan 02, 2022 10:38 am
Location: Nottingham

Front suspension rattly knocking noise over bumps

Post by Dean'o » Mon May 23, 2022 3:04 pm

Could just be loose dust sheild.

Dean'o
Member
Member
Posts: 166
Joined: Sun Jan 02, 2022 10:38 am
Location: Nottingham

Front suspension rattly knocking noise over bumps

Post by Dean'o » Wed Jun 08, 2022 6:10 pm

In relation to this topic all suspension parts renewed, unfortunately need a steering rack. Got play on the nearside.
Any ideas where to get steering rack from. Preferably new (not genuine). Any info much appreciated. Thanks

Phippy
Member
Member
Posts: 233
Joined: Sat Jan 30, 2021 2:12 pm

Front suspension rattly knocking noise over bumps

Post by Phippy » Wed Jun 08, 2022 6:41 pm

I have a similar knocking noice coming from the front end, seems more prevalent on the drivers side but could just be because i am closer to it. Knocking seems to happen most when going over uneven ground, like a wobbling noise, not so noticeable just going over a speed bump.

Have had new struts/springs, wishbones, wishbone bushes (Powerflex) and had all other bushings checked when work was done, none needed replacing but did upgrade the ARB ones anyway (Powerflex again).

My next thought was the engine mounts but i'm not sure how best to check them as all threads just seem to be for the Z4M, which assume can't be too dissimilar, will report back if i find anything in case it helps
2008 BMW Z4 3.0SI Sport Coupe
2013 VW T5.1 Camper - Built not bought

User avatar
enuff_zed
Lifer
Lifer
Posts: 14761
Joined: Wed Oct 26, 2016 11:05 am
Location: Attleborough, Norfolk

Front suspension rattly knocking noise over bumps

Post by enuff_zed » Wed Jun 08, 2022 6:44 pm

Phippy wrote: Wed Jun 08, 2022 6:41 pm I have a similar knocking noice coming from the front end, seems more prevalent on the drivers side but could just be because i am closer to it. Knocking seems to happen most when going over uneven ground, like a wobbling noise, not so noticeable just going over a speed bump.

Have had new struts/springs, wishbones, wishbone bushes (Powerflex) and had all other bushings checked when work was done, none needed replacing but did upgrade the ARB ones anyway (Powerflex again).

My next thought was the engine mounts but i'm not sure how best to check them as all threads just seem to be for the Z4M, which assume can't be too dissimilar, will report back if i find anything in case it helps
Have you checked that the strut braces are really tight. Just a quarter turn is enough for them to knock.
HQ of 'Norfolk Zed Rescue'.
Always happy to help if I can.

If the forum helped you, why not help the forum back. Thats the Z4 way! :thumbsup:
Image

Dean'o
Member
Member
Posts: 166
Joined: Sun Jan 02, 2022 10:38 am
Location: Nottingham

Front suspension rattly knocking noise over bumps

Post by Dean'o » Wed Jun 08, 2022 6:58 pm

I peeled the steering gaitor got hold of steering itself and its definitely got play in it. Compared to other side definitely feel the difference. I have renewed everything but.

Phippy
Member
Member
Posts: 233
Joined: Sat Jan 30, 2021 2:12 pm

Front suspension rattly knocking noise over bumps

Post by Phippy » Wed Jun 08, 2022 9:49 pm

enuff_zed, I will give it a go, do you mean the 3 bolts in the head or the bars that run to the centre by the windscreen?
2008 BMW Z4 3.0SI Sport Coupe
2013 VW T5.1 Camper - Built not bought

User avatar
enuff_zed
Lifer
Lifer
Posts: 14761
Joined: Wed Oct 26, 2016 11:05 am
Location: Attleborough, Norfolk

Front suspension rattly knocking noise over bumps

Post by enuff_zed » Thu Jun 09, 2022 7:32 am

Phippy wrote: Wed Jun 08, 2022 9:49 pm enuff_zed, I will give it a go, do you mean the 3 bolts in the head or the bars that run to the centre by the windscreen?
I mean the diagonal bars with a nut at either end.
HQ of 'Norfolk Zed Rescue'.
Always happy to help if I can.

If the forum helped you, why not help the forum back. Thats the Z4 way! :thumbsup:
Image

Dean'o
Member
Member
Posts: 166
Joined: Sun Jan 02, 2022 10:38 am
Location: Nottingham

Front suspension rattly knocking noise over bumps

Post by Dean'o » Thu Jun 09, 2022 7:35 am

No the actual steering rack itself

Post Reply