Suspension Knock - Worn Front Sway Bar Bushings?

weehe126 · 03-17-2019, 05:05 PM

Quote:

Originally Posted by sle39lvr

So this issue still seem to be there.

Knock is getting worse. It's more present when it's cold, less when warm outside.

I jacked it up again, couldn't notice anything being worn or lose. Any ideas?

PS: This is after new sway bar end links and new sway bar bushings.

Have you confirmed the 3 nuts for the front shock mounts are tight? What about the shock to mount nut under the cap?

03-18-2019, 08:22 AM

Quote:

Originally Posted by sle39lvr

I am going to drive with the links deattached, to see if the knock is outside of swaybar/links.

Did you try this yet?

If that's not it, I'd look at the upper strut mounts next.

ibanez78 · 11-11-2019, 08:29 AM

I know you have rules out swaybar bushings and endlinks but just wanted to throw out a test that I always do to rule out either of those. I will disconnect the swaybar links and go for a short drive, if the noise is gone then it's one of those 2 things, if it's still there then it's either strut mount or ball joint/tie rod.

colorado.e9x · 11-11-2019, 04:59 PM

I'm having this exact problem. Thought it was endlinks, so I ordered longer adjustable ones. Drove without endlinks for a week, no difference. With adjustable endlinks installed, still a knock. Retorqued everything except the strut to top mount so far (cause the strut tower brace is in the way) still a knock. Next step is replacing ball joints (I'm an xi so that'll be fairly easy)

fchen0125 · 06-04-2020, 06:39 PM

HI, Has anyone fixed this ? Having similar problem , replaced with new endlinks today and did not fix the knocking noise .... F36 with only 9k miles on it .

colorado.e9x · 06-04-2020, 07:25 PM

Nope. Clunk is still there. Haven't replaced ball joints yet though

sky82 · 03-12-2021, 10:53 PM

im having the same issues and thinking its endlinks also

at first i thought it was that the new sway bar was sitting too low with the coil overs so we raised the height of the endlinks but still getting it.

guess no one figure it out yet eh? im gonan drive with out the end links connected and see if it still happens

mweisdorfer · 03-13-2021, 09:27 AM

Quote:

Originally Posted by sle39lvr

Symptoms
When driven slow, over small undulations, I get a suspension knock from each/both sides from the front. This does not occur on lateral movements, only vertical ones at slow speeds.

My initial suspicion was - front sway bar links. Just replaced them and no difference.

Also double checked the strut tower nut at the top.

So I am guessing this could be worn front sway bar bushings?

Car
E90 @ 130K Miles.
Coil-over suspension lowered just below sport height @60K miles
M3 control arms @ 80K miles
New heavy duty steering rods @90K miles

Probably your sway bar links

bmw_solid · 03-19-2021, 07:26 AM

I'm also interested in this topic for my standard 330d SE '08 (I've also got a couple of threads about this on this forum!). Similar symptoms but I get a 50% thud-50% rattle noise over most medium to large road bumps/imperfections. Noise only at the front, back is whisper quiet and very damped over bumps!

Changed new SACHS shocks all-round, new wishbone and control arms, new ARB bushes and end links and new Lemforder Strut mounts and bump stops and even new inner/outer track rods, but still got suspension thud, knocking, rattle (what ever you wish to call it).

I'm curious if whether the garage torqued down the ball joint nuts for the arms and track rod and top strut nut...I've checked/torqued everything else myself but couldn't check these due to tool limitations.

I've also had a recommendation for the steering rack by a fellow member on this forum - apparently this can also cause a noise over bumps.

Nordic335M3 · 09-15-2021, 04:03 AM

Quote:

Originally Posted by bmw_solid

I'm also interested in this topic for my standard 330d SE '08 (I've also got a couple of threads about this on this forum!). Similar symptoms but I get a 50% thud-50% rattle noise over most medium to large road bumps/imperfections. Noise only at the front, back is whisper quiet and very damped over bumps!

Changed new SACHS shocks all-round, new wishbone and control arms, new ARB bushes and end links and new Lemforder Strut mounts and bump stops and even new inner/outer track rods, but still got suspension thud, knocking, rattle (what ever you wish to call it).

I'm curious if whether the garage torqued down the ball joint nuts for the arms and track rod and top strut nut...I've checked/torqued everything else myself but couldn't check these due to tool limitations.

I've also had a recommendation for the steering rack by a fellow member on this forum - apparently this can also cause a noise over bumps.

any updates mate?

11-11-2019, 08:29 AM	#25
ibanez78 Registered 2 Rep 2 Posts Drives: 2017 330i xdrive Join Date: Nov 2019 Location: Montreal iTrader: (0)	I know you have rules out swaybar bushings and endlinks but just wanted to throw out a test that I always do to rule out either of those. I will disconnect the swaybar links and go for a short drive, if the noise is gone then it's one of those 2 things, if it's still there then it's either strut mount or ball joint/tie rod.
	Appreciate 1 Quote

11-11-2019, 04:59 PM	#26
colorado.e9x eBay Special 3583 Rep 3,171 Posts Drives: E90 330xi Join Date: Feb 2018 Location: Western Slope, Colorado iTrader: (1) Garage List 2006 BMW 330xi [10.00] 2007 BMW 328xi [9.50]	I'm having this exact problem. Thought it was endlinks, so I ordered longer adjustable ones. Drove without endlinks for a week, no difference. With adjustable endlinks installed, still a knock. Retorqued everything except the strut to top mount so far (cause the strut tower brace is in the way) still a knock. Next step is replacing ball joints (I'm an xi so that'll be fairly easy) __________________ Common sense is a flower that does not bloom in everyone's garden
	Appreciate 0 Quote

06-04-2020, 06:39 PM	#27
fchen0125 Private 58 Rep 77 Posts Drives: 2015 435xi GC, 2020 X7-40i Join Date: Apr 2007 Location: New York, NY iTrader: (0)	HI, Has anyone fixed this ? Having similar problem , replaced with new endlinks today and did not fix the knocking noise .... F36 with only 9k miles on it .
	Appreciate 0 Quote

06-04-2020, 07:25 PM	#28
colorado.e9x eBay Special 3583 Rep 3,171 Posts Drives: E90 330xi Join Date: Feb 2018 Location: Western Slope, Colorado iTrader: (1) Garage List 2006 BMW 330xi [10.00] 2007 BMW 328xi [9.50]	Nope. Clunk is still there. Haven't replaced ball joints yet though __________________ Common sense is a flower that does not bloom in everyone's garden
	Appreciate 0 Quote

03-12-2021, 10:53 PM	#29
sky82 Private First Class 20 Rep 107 Posts Drives: 2007 E92 335i/2014 F15 X5 35D Join Date: Apr 2017 Location: Toronto iTrader: (0) Garage List 2007 BMW 335i E92 [0.00] 2014 BMW X5 35D [0.00]	im having the same issues and thinking its endlinks also at first i thought it was that the new sway bar was sitting too low with the coil overs so we raised the height of the endlinks but still getting it. guess no one figure it out yet eh? im gonan drive with out the end links connected and see if it still happens
	Appreciate 0 Quote

03-19-2021, 07:26 AM	#31
bmw_solid First Lieutenant 48 Rep 355 Posts Drives: E92 PreLCI 330d SE Coupe B.Red Join Date: May 2020 Location: United Kingdom iTrader: (0)	I'm also interested in this topic for my standard 330d SE '08 (I've also got a couple of threads about this on this forum!). Similar symptoms but I get a 50% thud-50% rattle noise over most medium to large road bumps/imperfections. Noise only at the front, back is whisper quiet and very damped over bumps! Changed new SACHS shocks all-round, new wishbone and control arms, new ARB bushes and end links and new Lemforder Strut mounts and bump stops and even new inner/outer track rods, but still got suspension thud, knocking, rattle (what ever you wish to call it). I'm curious if whether the garage torqued down the ball joint nuts for the arms and track rod and top strut nut...I've checked/torqued everything else myself but couldn't check these due to tool limitations. I've also had a recommendation for the steering rack by a fellow member on this forum - apparently this can also cause a noise over bumps.
	Appreciate 0 Quote