Instability Under Braking

[c3m]

After changing my tyres, I noticed that the place had a Hunter four wheel alignment system so I asked them if they squeeze me in without an appointment - the guy said that there's no point in doing it as the front lower control arm bushings were gone (he pushed the wheel back and forth when the car was stationery). So he said to get those done before doing the alignment.

I've also noticed some strange occasional instability when braking which doesn't happen always - only sometimes. It's usually when doing higher speeds (above 60mph) but also happens when at lower speeds (e.g., 10mph and apply brakes on an uneven road). At higher speeds, it feels like the car is suddenly shimmying to the left and then right, at lower speeds, it just pulls the steering to one direction. There's no vibration in the steering wheel whatsoever - all of this happens randomly and not every time I brake.

Can worn out front lower control arm bushings explain the observed instability? Any other suggestions?

Thanks.

[E30M3SE]

c3m said:

After changing my tyres, I noticed that the place had a Hunter four wheel alignment system so I asked them if they squeeze me in without an appointment - the guy said that there's no point in doing it as the front lower control arm bushings were gone (he pushed the wheel back and forth when the car was stationery). So he said to get those done before doing the alignment.

I've also noticed some strange occasional instability when braking which doesn't happen always - only sometimes. It's usually when doing higher speeds (above 60mph) but also happens when at lower speeds (e.g., 10mph and apply brakes on an uneven road). At higher speeds, it feels like the car is suddenly shimmying to the left and then right, at lower speeds, it just pulls the steering to one direction. There's no vibration in the steering wheel whatsoever - all of this happens randomly and not every time I brake.

Can worn out front lower control arm bushings explain the observed instability? Any other suggestions?

Thanks.

Yes.

[blondini]

c3m said:

Can worn out front lower control arm bushings explain the observed instability?
Thanks.

Yes, it's a no brainer.

[c3m]

Thanks, guys - will get those replaced and hopefully should eradicate the problem.

[Blue Oval84]

Yep, you'll notice it brakes hugely better with new control arm bushes.

Buy a quality brand though, don't go for cheap crap as it won't last two minutes.

[c3m]

Blue Oval84 said:

Yep, you'll notice it brakes hugely better with new control arm bushes.

Buy a quality brand though, don't go for cheap crap as it won't last two minutes.

I was going to get the OEM ones - aren't those good enough?

[bolide]

I put new BMW ones on my 525 two years ago and they need replacing again already. We have lots of speed humps round where I live

Nick Froome

[TheEnd]

You might find some powerflex ones about which are easier to fit than the rubber originals, and also stronger with a longer lifespan.

[Blue Oval84]

c3m said:

I was going to get the OEM ones - aren't those good enough?

Yeah they're fine, but if you want to save money get Lemforder ones, they make them for BMW but are normally a little cheaper.

I fitted Powerflex Control Arm Bushes to me Z4 and I hated what it did to the steering, far too twitchy and it fed back every imperfection in the toad surface back to the wheel.

Every other bush is Powerflex but for these I'm afraid I went back to Lemforder and haven't regretted it.

Euro Car Parts normally have a good discount offer on their website.