vibration through steering under braking?

[tbm1397]

hey folks.. had this problem a while back and thought it was the discs, so purchased a new set of discs and pads, fitted them and all seemed fine. problem returned and took the discs back under warranty and received another set. fitted them.. and again, the problem is still there. I have also replaced the ARB and the bushes and droplinks, so it cant be any of these..any help would be mucho appreciated..

 

[neo]

Don't know how old are your tyres, but that's the first thing that popped into my mind as I remember problem with a car I was driving a couple years ago.
With old tyres, vibration, especially when breaking and a lot less, almost none when accelerating. Thought alignment or something more complex, but after changing tyres - no vibration at all.
Try swapping back to front wheels just for test...

Cheers

 

[tbm1397]

just tried changing tyres around today and still the same.. anyone any other idea's?

 

[garywoods]

check the run out of the hub face which your disc bolts on to. the hub, and consequently discs might not be running true to the caliper? did you check when putting new discs on?

Gary

 

[tbm1397]

still got this annoying problem... changed tyres back to the front, still the same. checked hub face, all good.. and checked everything else i could just by looking... problem is still there. its really starting to p*** me off!

 

[spike]

Hi tbm

I had a similar problem with brake judder but it happened many months after changing the discs. The disc faces, particularly the back, were glazed over with a grey deposit, possibly due to me being very light on the brakes. I removed this with a coarse disc on an orbital sander, flatted the face of the pads on some emery paper taped to a piece of plate glass and cleaned everything up. Amazingly it completely cured the brake judder

Cheers Spike

 

[tbm1397]

will give that a try.. it was fine for the first 2-300 miles then it started. i dont use the car every day, so it might be a deposit of some sort..

 

[tbm1397]

tried rubbing down disc and pads with some fine emery paper today and problem is still there
What i did notice was that there was about a 2-3mm gap between the top locating arm of the pad and where it comes into contact with the caliper. the pads are not original audi they are OE quality pads from a motor factor, i'm thinking that the pads possibly aren't quite right.. this is the last thing that i can think it may be..