Brakes

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pete325i
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Post Wed Apr 05, 2006 8:40 am

Bit of a strange one this, although it may be obvious to some.
I had new disks and pads about 4 months ago and everything has been fine. Recently a wobble has developed under braking.
On first use of the car each day the wobble is less noticeable but gets worse as you drive.
I almost feels like something is moving, no idea what.

It's possible the disks could be warped I suppose but with them being relatively new and used normally I hope not.
Maybe I'll make a quick tool to test this.

I've installed new slide guide kits on both sides hoping this may fix what ever is wrong but no joy. (Only because when I changed the pads one of the bolts snapped and was replaced with an old one)


Any ideas would be much appreciated so thanks in advance. If you need any other details just ask.

Again many thanks



Pete
Simon
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Post Wed Apr 05, 2006 8:55 am

Were the discs cheap replacements?

Cheap discs will warp easily under a it of continious hard braking, been there myself, thought I'd save myself some money with some GSF £15 specials, was changing them after a couple of months.
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nasir325ic
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Post Wed Apr 05, 2006 9:03 am

I had a similar problem

have a look at my thread

http://www.e30zone.co.uk/modules.php?na ... ic&t=32100
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WerkdE30
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Post Wed Apr 05, 2006 9:39 am

hi mate im only a third year mecho but a wobble to me implies the whole car is moving when you have warped discs all i have ever seen is a pulsation thru the pedal. anyway id take it to your local mecho get him to put it on a hoist and check over your front end. the caster bar bushes frequently go on all old bmw's u test this by pushing the wheel upwards toward the front of the car and watchin the rubber bush to see if there is excessive movement or cracking.

i have just replace mine with the m3 offset bushes witch look a lot harder and change the position of it somewhat. havn't seen the result as yet as my gearbox conversion is only 50% complete.

hope this helps at all
Cava
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Post Wed Apr 05, 2006 10:03 am

I had a similar problem recently after fitting disks and pads from ECP.

I had a local BMW specialist check the car out (as I would'nt normally suspect brand new items) and they confirmed that the steering / suspension looked fine. I ended up changing both calipers after a second set of disks started to judder under braking after a few weeks use. The car is now running genuine BMW disks and pads with the replacement calipers and the problem has gone.

Just out of curiosity, I fitted the second set of disks to my other car (which run fine before) and the judder is now happening on that one - this basically proved that the disks were definately being warped by the old calipers.
Jackle
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Post Wed Apr 05, 2006 11:53 am

I had the same problem once, I figured it was warped discs so I changed the front discs and pads. All was fine for a few days then the wobble returned.
Then I changed the control arm bushes, this cured the wobble completely.
Get the car up on a set of ramps and take a look, you'll be able to see fairly easily if the rubber of the bush is deteriorated. They are easy enough to change.