steering wobble when braking

astigpangit · 07-01-2024, 09:04 PM

hi guys, 328i sedan here, i’ve been getting a steering wobble while braking, and i attached a photo of the driver side rotor (passenger side is the same) after some spirited driving. is something wrong with the rotors and/or pads with this uneven coloring/grooving? tires are balanced, alignment is good. guide pins and pistons have been greased. the calipers don’t seem to ever stick either.

edit: forgot to mention the pads seem to only make contact on the inside of the rotor, where the darker spot is

gaze2 · 07-02-2024, 02:20 AM

Do you have access to an IR camera? You can use one to check if the pads stick, or there is uneven contact. Or you could maybe if you are feeling masochistic let it cool a bit and use the completely safe method of using your natural senses - touch.
It could also be completely unrelated to the brake discs/pads, I chased steering wobble under braking and general instability in the front for quite some time, changed discs with pads, then tie rods, and finally new control arms fixed the issue (although all of the things mentioned were already shot or at their last legs).

scotthilly · 07-02-2024, 08:52 AM

Yeah, for me the issue was actually a worn bushing in the control arms. I don't believe these brakes are very susceptible to build up or other issues with the rotors.

If you're over 100k on the original control arm / bushings, I'd have that looked at.

astigpangit · 07-02-2024, 08:55 AM

haha damn i actually had another post about control arms. i’ve been on the fence between OE lemforder and the ( no longer TRW because of malaysia) m3 arms. looks like this will be my first “serious” mod, since it could affect the safety of driving the car. thanks for the input guys.

gaze2 · 07-10-2024, 03:21 AM

Quote:

Originally Posted by astigpangit

haha damn i actually had another post about control arms. i’ve been on the fence between OE lemforder and the ( no longer TRW because of malaysia) m3 arms. looks like this will be my first “serious” mod, since it could affect the safety of driving the car. thanks for the input guys.

Dont get m3 control arms, I installed mine last week, had a 500 mile road trip, and its pretty bad on rough roads. I am feeling apoplectic about them, on the one hand the car feels pretty good around corners, but also its a lot less comfortable, a lot of steering wheel feedback, especially with the state of the roads in my country...

Oh and pretty sure it just amplifies the downsides of bad suspension components, my front right strut is leaking a little, but it feels like its absolutely shot with the m3 arms. And also I barely got any negative camber with the new arms.

Jaronbwall · 07-10-2024, 09:00 AM

Quote:

Originally Posted by gaze2

Dont get m3 control arms, I installed mine last week, had a 500 mile road trip, and its pretty bad on rough roads. I am feeling apoplectic about them, on the one hand the car feels pretty good around corners, but also its a lot less comfortable, a lot of steering wheel feedback, especially with the state of the roads in my country...

Oh and pretty sure it just amplifies the downsides of bad suspension components, my front right strut is leaking a little, but it feels like its absolutely shot with the m3 arms. And also I barely got any negative camber with the new arms.

This is worst take on upgraded suspension parts for a 335i

The M3 arms are hands down better in every way and fixing worn out suspension comes with the territory. It's BMW sports sedan. If you want comfort buy another vehicle.
I had the same steering wobble and replacing the arms and tie-rods fixed the issue. Dried out/wore tires will also causes vibration at highway speeds. I'm at 122k miles and have a leaking front strut (waiting to replace it all). My car has been parked in a garage for the last 9 years. At this mileage and age stuff wears out.

whyzee125 · 07-10-2024, 01:31 PM

I can definitely attest to the fact that NVH is very subjective, not only to the individual but each car can react a bit differently too.

Most people say solid subframe bushings on this platform have zero additional NVH and in my experience that simply isn't true. That being said I'm pretty sensitive to it and I've run the M3 arms on 3 of my 4 e90s and my experience has been only positive every time.

Good call on avoiding the Malaysian TRW arms though; they are trash and consistently fail within a couple months.

07-01-2024, 09:04 PM	#1
astigpangit New Member 5 Rep 20 Posts Drives: 2011 328i base package Join Date: Jun 2024 Location: Pacific Northwest iTrader: (0)	hi guys, 328i sedan here, i’ve been getting a steering wobble while braking, and i attached a photo of the driver side rotor (passenger side is the same) after some spirited driving. is something wrong with the rotors and/or pads with this uneven coloring/grooving? tires are balanced, alignment is good. guide pins and pistons have been greased. the calipers don’t seem to ever stick either. edit: forgot to mention the pads seem to only make contact on the inside of the rotor, where the darker spot is Attached Images
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07-02-2024, 02:20 AM	#2
gaze2 Private 45 Rep 80 Posts Drives: E91 325i 6MT 2005 Join Date: Apr 2024 Location: Bulgaria iTrader: (0)	Do you have access to an IR camera? You can use one to check if the pads stick, or there is uneven contact. Or you could maybe if you are feeling masochistic let it cool a bit and use the completely safe method of using your natural senses - touch. It could also be completely unrelated to the brake discs/pads, I chased steering wobble under braking and general instability in the front for quite some time, changed discs with pads, then tie rods, and finally new control arms fixed the issue (although all of the things mentioned were already shot or at their last legs).
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07-02-2024, 08:52 AM	#3
scotthilly scotthilly 114 Rep 157 Posts Drives: 2011 BMW 335i 6MT Join Date: May 2018 Location: Chicago, Illinois iTrader: (0)	Yeah, for me the issue was actually a worn bushing in the control arms. I don't believe these brakes are very susceptible to build up or other issues with the rotors. If you're over 100k on the original control arm / bushings, I'd have that looked at.
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07-02-2024, 08:55 AM	#4
astigpangit New Member 5 Rep 20 Posts Drives: 2011 328i base package Join Date: Jun 2024 Location: Pacific Northwest iTrader: (0)	haha damn i actually had another post about control arms. i’ve been on the fence between OE lemforder and the ( no longer TRW because of malaysia) m3 arms. looks like this will be my first “serious” mod, since it could affect the safety of driving the car. thanks for the input guys.
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07-10-2024, 01:31 PM	#7
whyzee125 Brigadier General 1942 Rep 3,976 Posts Drives: Dinan stage 2 335i Join Date: Jul 2014 Location: Chattanooga Tn iTrader: (0)	I can definitely attest to the fact that NVH is very subjective, not only to the individual but each car can react a bit differently too. Most people say solid subframe bushings on this platform have zero additional NVH and in my experience that simply isn't true. That being said I'm pretty sensitive to it and I've run the M3 arms on 3 of my 4 e90s and my experience has been only positive every time. Good call on avoiding the Malaysian TRW arms though; they are trash and consistently fail within a couple months.
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