Car rocks back and forth after coming to a stop

ferocity02 · 06-20-2016, 10:22 AM

Noticed this recently... when I come to a full stop, the car gently rocks back and forth for a second before settling out. Seems like the suspension or something is overly soft.

Other than this I don't really notice anything out of the ordinary.

asquared · 06-26-2016, 01:50 AM

It could be possible that your control arm bushings need to be replaced. Usually you can look under the car and see if the bushing is leaking, but even if it's not, it still could be the culprit.

ritzzzzzwik · 06-26-2016, 02:31 AM

rear strut mounts & sub bushings (?)
mine did that quite a bit before I did a suspension refresh.

cdgatti · 06-26-2016, 06:31 AM

cheap fix to help this alot, but not totally eliminate it, is the Monroe rubber upper RSB.

BlindWolf187 · 06-26-2016, 09:02 PM

A bouncy suspension is frequently worn shock absorbers. Have you rules this out already? If not, see if you can bounce the car and see if the shocks are being actuated during the bouncing motion or if the struts are stationary when the bouncing is occurring (which would indicate that it is something like the control arm bushings)..
You all may know way more about this than I do, I'm just adding my thoughts to the pile..

mweisdorfer · 06-29-2016, 01:19 AM

Quote:

Originally Posted by ferocity02

Noticed this recently... when I come to a full stop, the car gently rocks back and forth for a second before settling out. Seems like the suspension or something is overly soft.

Other than this I don't really notice anything out of the ordinary.

When the front end moves up and down during a hard break, it means the struts are bad. You are probably going to have to replace the shocks and struts with most of the surrounding hardware.

ferocity02 · 06-29-2016, 12:05 PM

Quote:

Originally Posted by mweisdorfer

When the front end moves up and down during a hard break, it means the struts are bad. You are probably going to have to replace the shocks and struts with most of the surrounding hardware.

It doesn't move up and down, it rocks forward and back. Maybe I need to check the suspension linkages in the rear.

However it drives fine.

blackturbo · 06-29-2016, 12:16 PM

I had that similar problem. I replaced my control arms and did a shock and strut refresh with new mounts. Night and day difference. It minimized 95 percent.

ferocity02 · 06-29-2016, 12:28 PM

Quote:

Originally Posted by cdgatti

cheap fix to help this alot, but not totally eliminate it, is the Monroe rubber upper RSB.

What is this?

mweisdorfer · 06-29-2016, 12:45 PM

Quote:

Originally Posted by ferocity02

Quote:

Originally Posted by mweisdorfer

When the front end moves up and down during a hard break, it means the struts are bad. You are probably going to have to replace the shocks and struts with most of the surrounding hardware.

It doesn't move up and down, it rocks forward and back. Maybe I need to check the suspension linkages in the rear.

However it drives fine.

If the control arms in the rear were shot, it would probably squeak. Ball and socket joints and the lower, rear control arms are notorious for going on e90's somewhere between 75-125k.

I have not had a control arm in the front go bad yet. So, I don't know the signs and symptoms of those going bad. My guess would be the same in that of a horribly loud squeak.

mweisdorfer · 06-29-2016, 12:49 PM

Quote:

Originally Posted by ferocity02

Quote:

Originally Posted by cdgatti

cheap fix to help this alot, but not totally eliminate it, is the Monroe rubber upper RSB.

What is this?

That part sits on the top of the rear shock mounts inside the car.

It will stiffen up the ride, but if you have to do that to try and solve your problem, then rear shocks are gone to begin with.

You could take a rear shock out and test it to see if it's bad. One might only take 30 min to get out. They are very easy to take out and put back in. 2 bolts and out.

ferocity02 · 06-29-2016, 01:36 PM

Quote:

Originally Posted by mweisdorfer

If the control arms in the rear were shot, it would probably squeak. Ball and socket joints and the lower, rear control arms are notorious for going on e90's somewhere between 75-125k.

I have not had a control arm in the front go bad yet. So, I don't know the signs and symptoms of those going bad. My guess would be the same in that of a horribly loud squeak.

If I were to jack up the rear would it be possible to pull/push on the wheel and look for obvious play? Not sure if the system becomes rigid when its unsprung.

I'll also look for bad shocks but I don't think that's the issue. It rides like a dream!

mweisdorfer · 06-29-2016, 03:27 PM

Quote:

Originally Posted by ferocity02

Quote:

Originally Posted by mweisdorfer

If the control arms in the rear were shot, it would probably squeak. Ball and socket joints and the lower, rear control arms are notorious for going on e90's somewhere between 75-125k.

I have not had a control arm in the front go bad yet. So, I don't know the signs and symptoms of those going bad. My guess would be the same in that of a horribly loud squeak.

If I were to jack up the rear would it be possible to pull/push on the wheel and look for obvious play? Not sure if the system becomes rigid when its unsprung.

I'll also look for bad shocks but I don't think that's the issue. It rides like a dream!

I think you could see some play that normally should not be there. Remember the control arms are fitted with bushings. So, when those go bad, they squeak horribly loud. Some of the control arms are fitted with camber bolts that run through the bushings.

If you take the rear shock out compress it, and it doesn't come back into shape, it's gone

In terms of riding like a dream, people who drive the car 90% of the time can't recognize if their shocks & struts are bad because they get so used to how the car feels even when the suspension deteriorated over time.

If your shocks & struts have over 75k on them, their toast.

06-20-2016, 10:22 AM	#1
ferocity02 Colonel 553 Rep 2,085 Posts Drives: 2013 135is Join Date: May 2014 Location: USA iTrader: (8)	Car rocks back and forth after coming to a stop Noticed this recently... when I come to a full stop, the car gently rocks back and forth for a second before settling out. Seems like the suspension or something is overly soft. Other than this I don't really notice anything out of the ordinary. __________________ 2013 135is DCT Carbon Black Metallic
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06-26-2016, 01:50 AM	#2
asquared E39 134 Rep 286 Posts Drives: 2000 540i Join Date: May 2016 Location: Las Vegas, NV iTrader: (0)	It could be possible that your control arm bushings need to be replaced. Usually you can look under the car and see if the bushing is leaking, but even if it's not, it still could be the culprit.
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06-26-2016, 02:31 AM	#3
ritzzzzzwik Captain 234 Rep 723 Posts Drives: SO M4 MT Join Date: Oct 2014 Location: NOVA iTrader: (0)	rear strut mounts & sub bushings (?) mine did that quite a bit before I did a suspension refresh. __________________ 2007 335i E92 MT \| MFactory LSD \| Diff Brace \| MHD/Wedge Tuned\| BL Coils \| Stg2 lpfp BoostConcepts \| VRSF DPs \| VRSF 7" HD FMIC \| DCI \| VRSF CP \| BMW SSK \| Billstein PSS Coilovers \| M3 Control Arms \| Whiteline Rear SF Inserts \| SS brake lines \| Z4 35is Rotors \| Hawk 5.0 pads \| M219s + PSS \| PE Mod -SOLD 2016 M4 F82 MT
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06-26-2016, 06:31 AM	#4
cdgatti Colonel 260 Rep 2,547 Posts Drives: e90 328i Join Date: May 2011 Location: KY iTrader: (4)	cheap fix to help this alot, but not totally eliminate it, is the Monroe rubber upper RSB. __________________ OEM Black grill and Blackline tails - LCI halogens with Lux V2 coded as DRL - 3M Crystalline - BMS PBX - OEM Euro Airbox with K&N - Hardwired CTEK - Bilstein B6 w/OEM springs and SP perches - Conti DWS06 - HiFi-Helix DSP - JLAudio HD/XD-Morel - CD changer trim - AE optical out
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06-26-2016, 09:02 PM	#5
BlindWolf187 Private First Class 48 Rep 134 Posts Drives: 2008 E92 335xi 6MT Join Date: May 2016 Location: Denver, CO iTrader: (0)	A bouncy suspension is frequently worn shock absorbers. Have you rules this out already? If not, see if you can bounce the car and see if the shocks are being actuated during the bouncing motion or if the struts are stationary when the bouncing is occurring (which would indicate that it is something like the control arm bushings).. You all may know way more about this than I do, I'm just adding my thoughts to the pile.. __________________ 2008 335xi 6MT Coupe - Monaco Blue on Saddle Brown \| fully optioned
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06-29-2016, 12:16 PM	#8
blackturbo Captain 59 Rep 645 Posts Drives: 335i Join Date: Jul 2013 Location: vancouver iTrader: (1)	I had that similar problem. I replaced my control arms and did a shock and strut refresh with new mounts. Night and day difference. It minimized 95 percent.
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