OK I know another brake thread, but really you need to read this. Apologies it’s a long rant but bear with it.
Firstly a potted history of my time with my RS3. I purchased it end of July last year not from an Audi dealer. An 11 plate with @ 20K on the clock and about a week of Audi 3 year warranty left. First thing I did was book it into an Audi dealer for a check over and they replaced the brake fluid as per 3 year maintenance schedule. Report I got back said front brakes had 70% left. I assume they were talking about the pads as discs aren't usually an issue at this age.
I had already read a lot about the brake issues on these cars before purchasing. Mine had its original discs and I assume pads as well. So no 47i6 changes had been made. No B suffix on the disc rotors or bobbins on the calipers. I didn't have any squeal but the breaking seemed fairly pants as many others had noted. The disc surface was fairly poor and uneven and soon after purchasing the car I noticed the usual associated uneven braking through the wheel even at low speed almost like the brakes were binding. This culminated in a particular extreme brown trouser moment applying only moderate brake pressure slowing down from 140+. The car started slewing from one side to the other as one side gripped and then let go then the other side did the same and repeated on and on. No ABS triggered during all of this as I wasn't braking that hard. Much sawing at the wheel to keep it in a straight line later I was definite I had to get this sorted. I took out extended Audi warranty when I bought the car but after reading threads on this and other forums with other people reporting high speed braking instability and Audi doing nothing about it and saying it was expected I didn't bother trying to get Audi look at it. Anyway many other threads have convinced me the 47i6 fixes do absolutely nothing to resolve braking issues on these cars.
After reading 45btvc's thread on ASN it seemed EBC Red Stuff pads are far more up to the requirements on these cars so I ordered some. However I didn't fit them as I wanted to get the discs skimmed on the car using the Pro-Cut system to give a fresh flat surface for the new pads and also cure any brake disc imbalance into the bargain. Like others I also have the 70-80 mph wheel wobble which I felt sure was due to out of balance disc rotors not wheel imbalance.
Anyway due to being busy at work and the other usual excuses I didn’t get around to doing any of this until the beginning of this month when the pad wear sensor triggered (wrongly as it turned out but that’s on another thread). With over 26K now on the clock I checked the disc thickness as best I could and read over 31mm near the outside of the disc (new these discs are 32mm with the minimum allowable being 30mm) so worth skimming as it only takes a few thou. This would be significantly cheaper than replacing the discs for me to prove if it is the discs causing wheel wobble and other associated problems that I will go into later. However after I got to my nearest Pro-Cut garage on Friday last they told me nearer the centre they had measured the discs at just over 30mm so not worth skimming.
Needing the brakes sorting quickly I called around some Audi dealers and thanks to Reading Audi Parts dept. for getting a set in for the next day (Saturday) so I could change them myself.
Here is my offside disc. notice the deep groove toward the centre. This is what made the disc too thin to skim. The nearside disc was in the same poor condition.
Here is what caused the damage. Audi spec Pagid pads. Notice the spots on the pads. These are what scored my discs so badly. They look like how the pad material is attached to the metal backing due to the regular pattern on both pads. As you can see there was still sufficient material left on the pad above their minimum of 5mm for this not to have happened. If you have these pads fitted to your car I would personally recommend you get the replaced with something more suitable as soon as possible before they eat your discs.
With the disc off the inside surface was in worse condition than the outside. Looks like the inside pad does most of the work. this was the same on the nearside disc. Look at the wear toward the outside of the disc.
So my findings with the new discs/ Red Stuff pads so far:
Wheel wobble at 70-80 now gone. I know some people are having their wheels balanced on the car using Hunter systems to cure this problem but you are probably balancing the wheel to cure unbalanced brake discs. If you get the discs running aligned to the hub using Pro-Cut skimming they should effectively be balanced. If the rotation of a Hunter balanced wheel is changed by being rotated when the wheel is off the car during a service etc and it’s the brake disc causing the problem then you will most likely unbalance the wheel/ disc/ hub relationship again.
General braking Sooo improved. No binding, smooth, progressive and much better pedal feedback.
I mentioned earlier about some other associated problems hopefully being cured with skimming my original discs. Well since I have owned the car I was very disappointed with the general front-end handling. I was getting quite a lot of suspension patter from the front, imprecise steering feel and a weird slight pull to the left or right depending on road camber. I was suspecting geometry problems or worse case suspension failure or wear. Well after changing the discs all these problems have gone. I really cant convey how much better the car is to drive. Feels like my old 2006 A3 2.0 TFSI Sportback Quattro SE, loved that car as the suspension was so sorted. Cant believe crappy discs could cause so many problems.
I’ll see how things go with the new discs with the Red Stuff pads. Hopefully there wont be uneven wear causing some of these problems to return but I will be straight back to the Pro-Cut garage to get them aligned (and balanced) to the hub if I get the slightest sniff of a problem.
Edited by Duke3D, 12 January 2015 - 08:25 PM.