[e90xxxx]

Hi guys,

I drive a 2005 320D E90.
I've noticed in the last 3 months that when I brake the steering wheel vibrates and it's getting worse. I don't notice any vibrations anywhere else other than in the steering wheel.


It happens at low speeds ~50km/h and high speeds 120km/h

All pads were replaced about 3,000km ago. Rear calipers were also replaced at the same time.
I don't drive the car much - maybe 220km every 2 weeks (I get the train to work, visit my parents once every 2 weeks ~100km away).

The front drivers side tyre has a slow puncture - it goes from 32psi to 27psi in 2 weeks.
The vibration is still there immediately after I pump it.
I also can't find where the injury is in the tyre - there is a cut in the sidewall but it doesn't look like it's deep and so I'm not confident this is the issue (although a possibility?).

My ideas:
Tyres? Could the nick in the sidewall cause this?
Solution: 2 new front tyres fitted (Cost ~€120)

Tension strut/Lower control arm replacement?
Is there any way to check if these need replacing?
Solution: Replace (Cost ~€150 + Tracking €50)

Tracking?
Could the car (wheels?) be out of alignment and need to be tracked?
Solution: Bring to garage to get tracking fixed (~€50)

Balancing?
Wheels need balancing?
Solution: Bring to tyre fitters to balance, or maybe just get new tyres altogether (Cost ? / ~€120)

Anything else to suggest?

My initial thoughts also were a warped rotor, but after some reading some people suggest that modern rotors do not warp.

Thanks for any help!

 

[dergside]

There are 3 most likely reasons:

• wheel balance - if this was a problem you would probably have some level of vibration all the time.
• buckled wheel - would likely be visible on a wheel balancer.
• a tyre defect such as a bulge, most likely on the tread area - again, this would likely be causing vibration all the time, and progressively worse at higher speed.
• worn brake pads and/or warped discs - this would cause vibration primarily when braking. Since pads have recently been replaced then its a little more likely that the discs are warped, unless the pads were cheap and nasty.

I think the e90 has CBC where the brakes are used as part of the stability system so they do more work than you realize.

 

[Reuben]

Warped discs would cause vibration in steering at all speeds and would also give noticeable feedback in the pedal, most likely front radius arm to chassis bushing, best and most cost effective to replace with powerflex bushes, search PFF5-401

Wear in this bushing creates a feedback loop as the wheel moves back (due to slack in the bushing) under braking which the abs then tries to correct for, essentially the abs is causing the judder as it applies and releases the brake rapidly