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Nebone
02-04-2008, 09:48 AM
*I posted this in Brake forum but no responses yet...*

So I've been having this vibration from front brakes. It does not shake the steering wheel, only creates vibration in the pedal. Happens at low and hi speed and specifically when coming to a stop. If I wham on the brakes at high speed, they are smooth for a day then the vibration comes back.

Brakes are:

12.3 Slotted ECS Rotors w/ TT Cariers
Mintex Red Box Pads
New Brake Fluid (been shaking before)

I think it has to do something with the slots, might be caked up with dust and are uneven on the pad.

Rotors have couple thousand miles on them and don't have the symptoms of being warped?

AudiSport12
02-04-2008, 10:03 AM
My guess would be your rotors are warped.

My pops put some slotted rotors on his A6 4.2 and within a couple thousand miles they had warped.

317ssayzarc
02-04-2008, 10:10 AM
if you want you can come by and ill take it for a drive...

ill give a real first hand diagnosis [up]

onemoremile
02-04-2008, 10:10 AM
Rotors almost never warp. Seriously. Stoptech even has a white paper on the subject.

What feels like warped rotors are usually pad deposits on the rotor. Even pad deposits are normal and are often referred to as the fire ring by track sluts. Uneven pad deposits are usually cause by lengthy braking with the brakes held at a stop light. This embeds more deposits in one area and the thickness difference causes the pedal to pulse.

Read Stoptech's technical article on bedding brakes and on warped rotors. I would take 100 or 200 grit sandpaper to the pads and rotors and then bed them in again. The only time this didn't fix the issue for me was when the rust scale on the hub was causing the rotor to sit a bit crooked. Sand or Scotchbrite the hub area and rotor mating surface too.

Nebone
02-04-2008, 01:47 PM
They definitely don't seem to be warped. When I hit them hard at high speed, they are very smooth after that for a while then vibrations come back. It must be pads caked up in there. A good cleanup won't hurt.

I'll have Jake take a look at it, he's local.

onemoremile
02-04-2008, 02:12 PM
My drilled and slotted rotors had to be cleaned out a few times. That is why I've got smooth rotors now.

whoace
02-04-2008, 03:04 PM
can u push/pull the caliper. should have some play. if not, sliders probably seized up on you.

Nebone
02-05-2008, 11:16 AM
can u push/pull the caliper. should have some play. if not, sliders probably seized up on you.

Thats the reply I received on VWVortex. I will check this first and lube them up.

dano
02-11-2008, 12:08 PM
Wheel bearings or you have torqued the lug nuts too tight. Lug nut torque is around 90ft/lbs.

Nebone
02-14-2008, 10:36 PM
I have a bad tie-rod end on the passenger side. Could that cause the vibration in brake pedal rather than steering wheel?

Nebone
03-20-2008, 09:18 PM
Replaced the Tie Rod today. Boot was done but the ball joint had no play in it.

Greased the slider pins and cleaned the slots on the rotors and the vibration is still there.

I still don't think its warped rotors because the vibration still occurs almost when coming to a stop.

whoace
03-20-2008, 11:28 PM
When you had the calipers off, did you check if the pistons were seized? You can also try adding a chamfer to the pads if they aren't already.

Nebone
03-22-2008, 11:14 PM
I didn't pull the calipers unfortunately; just pulled the pins. I did notice, that on one side the rotor can turn freely with caliper on and on the other side it is pretty tough to move.

I will check the chamfer and possibly change out the Mintex pads I have with something else.

It brakes strong so I wouldn't suspect a seized caliper.

Burntaudi
03-22-2008, 11:19 PM
It sounds like a pad deposits.

whoace
03-23-2008, 01:26 AM
I didn't pull the calipers unfortunately; just pulled the pins. I did notice, that on one side the rotor can turn freely with caliper on and on the other side it is pretty tough to move.

I will check the chamfer and possibly change out the Mintex pads I have with something else.

It brakes strong so I wouldn't suspect a seized caliper.

When a caliper seizes it will still move out. The hydraulic pressure will force it out. The problem is that it won't go back in. You would get vibrations until the pads wear enough to no longer contact the rotor.

Yaktizzle417
03-23-2008, 08:13 AM
My drilled Zimmermans are doing the same..

It seems like the holes themselves are filled completely with dust, whats the best way to get them out?

I have a dremel.. which automatically makes me able to do anything.

=] (/joke)

lunamarA4
10-20-2008, 11:44 PM
When a caliper seizes it will still move out. The hydraulic pressure will force it out. The problem is that it won't go back in. You would get vibrations until the pads wear enough to no longer contact the rotor.

how do u go about fixing this problem????[wrench]