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20A4Audi1.8t01
09-02-2009, 08:42 PM
At about 30-35 mph when applying the brakes my car shakes the shit out of what seems to be coming from the passenger side wheel well. Any idea what could be going on here? Control arms?

Tyler

yung_wallace B5
09-02-2009, 08:44 PM
warp rotor?

20A4Audi1.8t01
09-02-2009, 08:51 PM
shouldnt be, replaced all 4 rotors with Adams slotted/dimpled not long ago.

FYI the front rotors are S4's

ghost6303
09-02-2009, 08:56 PM
how long ago? go thru any puddles while the brakes were hot? maybe there was some rust or something on the hub so they arent sitting flat. either that or your guide pins might be sticky.

20A4Audi1.8t01
09-02-2009, 09:04 PM
Prob about 2-3 months ago maybe? Puddles that cant be avoided, yes. So you guys dont think its a bad control arm? As some of you may know I had to use S4 uprights, think maybe their could be an issue with the passenger one? [confused]

Stubek
09-02-2009, 09:08 PM
I got brakes once on my Z28, tracked the car the next day and warped them. Check those rotors.

20A4Audi1.8t01
09-02-2009, 09:16 PM
that sucks man! I dont track my car nor do I ever intend to. I spiritly drive once in awhile and their was a time where I had to mash on them with 4 people in the car while they were still kinda new, IDK if that may have had anything to do with this shaking issue over what little time Ive had them on the car? I will check them first thing tom though!

kevin12
09-02-2009, 09:35 PM
Yeah most of the time when there is vibrations when braking coming from the front its a warped rotor(s). Is it worse when stopping from a higher speed?

adrenaline486
09-02-2009, 09:36 PM
Check your bearings. Different pressure on the wheel thats bad wheel will cause the car to shake. Usually its more common when you turn to put more pressure the bad wheel it but when mine was bad, breaking sometimes made it worse. Though that is a long shot, my first guess would be bad/warped or improperly installed rotors.

20A4Audi1.8t01
09-02-2009, 09:49 PM
Yeah most of the time when there is vibrations when braking coming from the front its a warped rotor(s). Is it worse when stopping from a higher speed?

Yes and no, sometimes it doesnt even shake. Other times from about 50 mph down to 30 mph it shakes and sounds like something is knocking from the passenger wheel well. On the highway not so much, but I havnt been on the highway lately. I will Friday though, suppose I could see what happens and report back.

I shoulve also noted that my brake reservoir is cracked and some fluid has leaked out and is possble that their is air in my brake lines. Will be ordering a new reservoir asap! But could this have anything do with the possible warping??

petera4
09-02-2009, 10:14 PM
has this been happening since you put rotors on? if so did you reinstall the hub centric rings correctly?

20A4Audi1.8t01
09-02-2009, 10:24 PM
No hasnt happened since day 1, this has happened over a period of a few months. I didnt install them Shawn did (A4ringedONE8T) from 1552. Ill be going back down in a lil while to get more work done so Ill have him check it out! Was hoping to get the issue resolved before I drive 2 hrs in case I needed to order something.

kastro
09-02-2009, 10:41 PM
if none of the above works.. long shot.. but.. some coated rotors + NOT breaking them in correct = gets the coating sludged unevenly on the rotor, causing the vibration. also.. do u hear any noises..or just vibration.

Ado
09-02-2009, 11:41 PM
if i was you i would check out the rotors. and also make sure your lugs are torqued down to 90lbs.

zrowcool
09-03-2009, 05:13 AM
tire titty?

20A4Audi1.8t01
09-03-2009, 07:16 AM
if none of the above works.. long shot.. but.. some coated rotors + NOT breaking them in correct = gets the coating sludged unevenly on the rotor, causing the vibration. also.. do u hear any noises..or just vibration.

What kinda noises? I hear cricket like noises when driving along, but thats just the pads rubbing. When applying the brakes I hear the pads going over the slots. Thats the only noises I hear coming from the rotors. Otherwise I just get this terrible shaking from the what feels like the passenger wheel well.

20A4Audi1.8t01
09-03-2009, 07:21 AM
I will make sure everythings torqued down as well Ado.

I doubt it could be a tire titty.

20A4Audi1.8t01
09-03-2009, 09:37 AM
Just got back from Eurotechnik, Brake fluid was at the min line so we topped it off. The shaking/vibration happens when the rotors heat up. That a case of warped rotors?

kevin12
09-03-2009, 10:20 AM
Just got back from Eurotechnik, Brake fluid was at the min line so we topped it off. The shaking/vibration happens when the rotors heat up. That a case of warped rotors?

Well if you had air in the lines the peddle would pratically go to the floor so that's def not your problem and you said it was only at the min so you're okay there. Warping occurs when brakes over heat but they just wouldn't make noise/vibrations only when heated up. So it's hard to say you just need to pull the wheel and rotor off and take a look it. It's not really a hard to thing to do and it would definitely give us more insight to the problem.

20A4Audi1.8t01
09-03-2009, 10:37 AM
Ill have to take it back up their, they were pretty packed with cars in the garage today. I dont have a proper jack nor tools.

joes_a4
09-03-2009, 02:50 PM
my car does the same thing too. except mines come from the front driver side. i think its warped. im going to be getting some new rotors tomorrow so if anything changes ill let you know.

20A4Audi1.8t01
09-03-2009, 02:53 PM
thanks man eagerly waiting! bugs the shit outta me! Your steering wheel shakes too?

whoace
09-03-2009, 07:27 PM
Check the temp of the wheel after driving. Is it hotter than the others? Could be a seized caliper.

Kyle H
09-03-2009, 07:46 PM
What do you mean heated up? Is it only when you're doing multiple 80-0 stops or just after you've been driving a while it starts to wobble?

Also, warped disks don't happen:
http://www.stoptech.com/tech_info/wp_warped_brakedisk.shtml

Jack up the front of your car and give the tires each a good shake, rule out your suspension components. I'd guess it's a TRE or control arm... does your car pull to the side or still go straight?

20A4Audi1.8t01
09-03-2009, 07:50 PM
What do you mean heated up? Is it only when you're doing multiple 80-0 stops or just after you've been driving a while it starts to wobble?

Also, warped disks don't happen:
http://www.stoptech.com/tech_info/wp_warped_brakedisk.shtml

Jack up the front of your car and give the tires each a good shake, rule out your suspension components. I'd guess it's a TRE or control arm... does your car pull to the side or still go straight?

When the rotor heats up after Ive been driving and braking for awhile it starts to shake. The car does pull very little to the right, almost cant even tell. Had it aligned when the Coils went on prob bout 3 months ago as well.

Kyle H
09-03-2009, 07:55 PM
Well it sounds like the problem occurred between 3 months ago and now... It could be a siezed caliper on the pass. side, that would cause it to pull to the right and would probably shake from the torque of it trying to stop... I still think it's something in your suspension or maybe driveline (cv joint, wheel bearing?)

20A4Audi1.8t01
09-03-2009, 08:13 PM
could be a wheel bearing, I would hope it wouldnt be a damn cv joint as I had both axles replaced (rebuilt) with new cv boot kit about 3 years ago or so.

This never has happend since the S4 brakes with Adams slotted/dimpled rotors went on about 3 months ago.

kevin12
09-03-2009, 08:33 PM
Also, warped disks don't happen:
http://www.stoptech.com/tech_info/wp_warped_brakedisk.shtml



The disc itself isn't warped but the surface can become uneven due the brake pad build up in different spots hence causing the vibration. Most people just call this warping whether you want to get technical or not lol.

But it could be a suspension component seems weird that it only happens after driving for awhile though.

Don't think its a bad wheel bearing either though. I've never had one really pull the car badly. It usually hums and gets louder as you turn to that side. Plus if its the original bearing that means it wasn't installed wrong so premature failure is out on that one. They also just don't suddenly fail either, they slowly get worse. Meaning something you would start to notice and then feel the progression.

My guess is uneven rotor wear or when the caliper is being heated up from driving it that its causing it to seize.

20A4Audi1.8t01
09-04-2009, 03:26 PM
True well cross the wheel bearing off the list. I got the S4 uprights with about 80k on them. Hope all it is is just a "warped" rotor.

andyrew
09-04-2009, 03:31 PM
Take it to a brake shop that can turn the rotors on the car. They will tell you if its bad or not. You should be out the door with freshly turned rotors for under $100.


GL

kevin12
09-04-2009, 03:33 PM
Take it to a brake shop that can turn the rotors on the car. They will tell you if its bad or not. You should be out the door with freshly turned rotors for under $100.


GL

Agreed. If you can't really take a look at it yourself then this is definitely what I would do [up]

onemoremile
09-04-2009, 03:38 PM
I would guess it is a suspension problem. Worn links, bushings, bearings, etc can all cause this to happen.

If it were a hydraulic brake problem the car would have pulled to one side due to uneven pressure.

Rotate the tires front to back and see if it still happens. Check the suspension out and use a pry bar to flex the bushings and links. Something is very wrong somewhere.

aREValo
09-15-2009, 10:05 PM
i had this problem with my a4 and what it was on mine was the upper control arm bushing... but generally it's the rotors or wheel bearing..

20A4Audi1.8t01
09-15-2009, 10:11 PM
I see, it seems like its coming from the axle area but could very well be the control arms. I have been procrastinating, I will get it checked out soon and take everyone's insight! [up]

somebody5788
09-15-2009, 10:38 PM
Usually if it's related to pushing the brakes then its warped rotor's. Mine however pulls a different way every time I hit the brake. I'm not really sure what that means. I also think my rotor's are warped. I will be turning my rotors and changing: control arms, sway bar links, and a CV shaft tomorrow. I'll let you know if I find anything else obvious and if it goes away.

20A4Audi1.8t01
09-16-2009, 09:13 AM
Thank you eagerly waiting!

20A4Audi1.8t01
09-22-2009, 03:09 PM
Usually if it's related to pushing the brakes then its warped rotor's. Mine however pulls a different way every time I hit the brake. I'm not really sure what that means. I also think my rotor's are warped. I will be turning my rotors and changing: control arms, sway bar links, and a CV shaft tomorrow. I'll let you know if I find anything else obvious and if it goes away.

any news?

onemoremile
09-22-2009, 05:06 PM
Usually if it's related to pushing the brakes then its warped rotor's. Mine however pulls a different way every time I hit the brake. I'm not really sure what that means. I also think my rotor's are warped. I will be turning my rotors and changing: control arms, sway bar links, and a CV shaft tomorrow. I'll let you know if I find anything else obvious and if it goes away.

Don't bother touching the rotors unless you can feel the brake pedal pulsing. It is most likely worn bushings in the steering or suspension.

stack
09-23-2009, 05:24 AM
you prob got warped rotor thickness varation