Shake when braking....

[bimmer_E30]

Hey,

it feels that the steering wheel on my E30 has lots of play...when i brake at any speed( Light braking) my steering wheel shakes really badly, sometime i don't notice the shake when i brake really hard...and when i almost come to stop it feels that the car will go back and forth...like juggles(or whatever u call it lol).

what do i have here, failur of: Rotrors?, Balljoints? and i think i have a bad wheel bearing too since my E30 feels like i am riding in a train when accelerating.

who gives? :loco:

[whodwho]

Sounds like it is originating from warped rotors but any play in the suspension (ball joints, tie rod ends, CABs) can exaggerate it.

Put the car up and grab the front wheels at 9 and 3 and push and pull and see how much play is in the tie rod ends. You can try to pry the control arm by the ball joint and see if they have play. And look at the CABs and see if the rubber is cracked.

[xwill112x]

get your rotors turned. that'll fix the prob.

[Wh33lhop]

They're not warped, you just have uneven pad transfer. It amounts to the same thing, more or less.

I can get new brembo blanks for about $25 apiece, so I'd rather do that then get them turned. But do one or the other.

[bimmer_E30]

just to add that there is a clunk noise(comming from the steering wheel) when braking too...

[Miasma]

Are the control arm bushings known to be good?

[kenika65]

bimmer_e30 I guess I just realized you dont have much mechanical knowledge...

humm well if the problem is only there when you brake then 9-10 its the rotors...

and if like you said you have other issues even when not braking then you have suspension failure...

easy way to find out... Jack Stands...

And I Love R3V....

[Philo]

Wow. There is a lot of assumption in this thread. Everyone automatically said bad rotors.

I, unlike the auto geniuses above, would like some more info on the problem before I weigh in. Is the vibration only felt when braking, or is it always preset (even the slightest bit)? I would do a simple routine check of the steering components. Check for play in the wheels from side to side, and top to bottom. Also, inspect CA bushings, which is typically the problem in these scenarios.

[Wh33lhop]

Wow. There is a lot of assumption in this thread. Everyone automatically said bad rotors.

I, unlike the auto geniuses above, would like some more info on the problem before I weigh in. Is the vibration only felt when braking, or is it always preset (even the slightest bit)? I would do a simple routine check of the steering components. Check for play in the wheels from side to side, and top to bottom. Also, inspect CA bushings, which is typically the problem in these scenarios.

Well whoopdee-fucking-doo. Seems you've got it covered your highness, I'll let you take it from here.

[Philo]

Whoa, slow it down there killer. I was just pointing out the fact that many people in this thread (not specifically you) made a diagnosis without gathering more info. I'm here to help out the OP. If you want to have a temper tantrum, PM me.

[whodwho]

If it shimmys when braking and not when your not then the rotors are warped. I just put some new rotors on mine for this very reason and now all is good.

Also don't have them turned especially if they are just stock blanks as they are cheap new and thin enough to start with and having them any thinner and they can just warp again sooner.

[jlevie]

I'm with Philo. There isn't enough diagnostic information in the original post to be able to conclusively state what is causing the problem. My suspicion would be worn a worn front suspension (control arms, CABs, tie rods, wheel bearings, and shocks) aggravated by uneven pad deposits on the rotors or by rotors that aren't sitting flush on the hubs.

[Wh33lhop]

If it shimmys when braking and not when your not then the rotors are warped. I just put some new rotors on mine for this very reason and now all is good.

Also don't have them turned especially if they are just stock blanks as they are cheap new and thin enough to start with and having them any thinner and they can just warp again sooner.

99% of "warped rotors" are just rotors that have been stopped on hot, transferring an uneven surface of pad onto the rotor creating an uneven friction surface (non-uniform mu over the whole rotor) which leads people to believe that the rotor's warped. So no, they're most likely not warped, lathing them down is fine as it'll get rid of the transferred pad layer and it won't make much of a difference.

Regardless, I'd say get new rotors because there really isn't much of a price difference.

[whodwho]

At least we agree on the new rotors :D

If it was pad material which very well could cause issues don't you think it would remove these deposits after a couple stops?

[Wh33lhop]

At least we agree on the new rotors :D

If it was pad material which very well could cause issues don't you think it would remove these deposits after a couple stops?

Here's a good stoptech article on the subject:

http://www.stoptech.com/tech_info/wp_warped_brakedisk.shtml

Sorry for clogging the thread as this may very well be only tangent to the issue