Any experts on brakes out there?

[ollys]

Sorry for the essay:

The brakes on my car have been poor for a while now. It has RS6 front calipers and B7 RS4 discs and B7 rear brakes. All this was done in the previous owners' ownership and put on about 3 years ago and 27,000 miles ago.

The brakes were fine till recently, when they started to make a LOT of squeaking and loud groaning. The squeaking mainly coming to a complete stop in traffic. The groaning (?) could be heard often when applying the brakes on the motorway after not touching them for a while at speed. Quite disconcerting.

Added to the that the pedal has been getting longer and longer! A couple of times the abs kicked at the bottom of the pedal travel again coming to a complete stop in traffic (but I was no where near from skidding)
.

Just changes the front discs (to Phaetons) and pads at MRC. Thought this would cure all the issue, but if anything it was slightly worse at first, esp the abs thing which seemed to kick in at EVERY stop from any speed on the way home (almost unbearable). Anyhow the brakes have bedded in a tad and the abs occurence has reduced although not cleared. Doug thought that might be some dirt / oil on the abs ring (MRC changed a split CV boot at the same time as the front discs and pads). However the pedal is still long - sometimes there is an initial bite put push a bit hard and the pedal seems to travel without doing much (its a weird sensation).

Does anyone have a thoughts on what's going on? I am back at MRC this sat to have new fluid, braided lines, check the abs rings and possibly new master cylinder (I have been trying to get my hands on the MTM upgrade M/C but no joy so far). I hope this will fix it, but I really can't afford to drive away and it be the same. Therefore can anyone suggest what's up - do my front calipers need some attention perhaps.

Sorry for the long post - the brake set up could be fabulous given the components in question, but sadly its nothing close. I would like to get this sorted.

Olly

[MOR8A]

Where are you based?

Sounds like failing master cylinder to me.

[ollys]

Where are you based?

Sounds like failing master cylinder to me.

I am in SW London.

Always suspected the M/C. Will change it I think. Really think that it's not quite up to the job or has got tired with the bigger brakes. I am sure that's why MTM (used to?) offer an upgrade kit which increases the bore to match that of the B7 RS4. I asked QST if it was available but Kim was unaware of it - how's that for MTM's uk agent? He further seemed to think that it was not necessary. I'm not so sure and have been trying to get one from MTM directly in Germany.

Olly

[MOR8A]

Get the master cyl changed (as you say) Ensure the brakes are bled (properly, furthest from the m/c first) would be surprised if your problem does not go away. Let us know.