I'm trying this again, nobody responded to previous thread. Wife's car has what she describes as a shuttering feeling in the brakes under normal heavy braking from highway speed. Was told by dealership the rotors were glazed... pads are fine, just rotors need replacing... $2000.00
I'm throwing down B.S. card and trying to resolve. I drove car the other day. Did some aggressive braking from 60 mph, 30 mph... different speeds. It feels like ABS activation... the pulsing feeling is the same speed, no matter how fast the vehicle is moving, not like a warped rotor where it would feel slower at slower speeds. I'm not talking about track style heavy braking, just normal hard braking like coming to a red light a little fast or coming off freeway. Any thoughts???

 

New front rotors should not cost $2,000. Get a second opinion from an independent
shop.

 

Before replacing the rotors, I'd have someone monitor the wheel speed sensors during braking and see if any one of them "drops out" or suddenly shows a lower speed than the other 3. This will NOT turn on an ABS warning light (the module doesn't know anything is wrong). IF one drops out or shows a lower speed, the ABS will actuvate thinking that wheel is starting to lock up, when it really isn't. Feels like the pedal is "buzzing" and sounds like almost a grinding type noise? That's what I get from what you said. Run into this all the time, especially on Chevy/GMC trucks at work (indy shop). If all looks good, then it's back to rotors but as you mentioned, that would change frequency with speed changes. Unless they're hardened from heat they may be able to be machined if the minimum thickness isn't exceeded. Sometimes rotors get hot spots and the metal is so hard in those areas the lathe cutting bit skips right over it with out cutting a thing. That would be substantially less than $2,000 which I agree, is way to high a price for even all 4 rotors plus labor. I'd think you could find some good aftermarket rotors that AREN'T made in China for a whole lot less than $2K.
I worked at an Audi dealer for 5 1/2 years and always preached "Genuine OEM Audi only" but in the 2 years I've been at an indy shop I have seen the light and changed my tune! lol Well OK, certain things I'd go Audi (or Ford, Dodge, Toyota, etc) only. Things like electronic parts for example and of course, the parts you have no other choice on.

 

Hi. My A6 is behaving similarly. Were you able to fix the pulsating brake problem? Appreciate any learnings.

 

Had that same problem with my 08 Infiniti M35. It was covered under warranty and they replaced rotors and pads. That fixed it. Fast Forward, we now have a 2016 A6 2.0. That problem occurred again at about 13000. Dealer was able to replicate the condition and they replaced rotors and pads under warranty. If your car is out of warranty, I'd look into a reputable repair shop such as STS, Goodyear, etc. Disc brakes are not overly complex. Unless the rotors are below minimum thickness, they should be able to be turned to absolute smoothness. Are the brakes the OEM or have they been serviced?
Good luck with it. Hope it works out.