Puzz1

Starting to feel some vibration when braking on the highway (ie exit ramp stuff) and can feel it vibrating especially when the ACC slows the car as well. Car has only 19,500 miles. Is this common? Most of my driving is around town but I'm not hard on the brakes by any stretch.

LexusLSguy

Yes, it's a heavy car. Pulsating pedal means deposits on the rotors. See all the other brake threads...

Forcefed4door

Try to downshift the car to slow down. I drove many manual cars, and now many autos. I always down shift before turns and stops. Good chance you'll never get a warped brake rotor driving in this fashion. Plus it gives you something to do 😀

LexusLSguy

99% of the time it is not a warped rotor. This is a very common misconception. The pulsating sensation comes from the pads leaving deposits on the face of the rotor not actually warping the rotor. If you actually warped a front rotor you would be towing the thing in to a shop.

MP4.2+6.0

+2 or 3 now.

And, don't be sure it is brakes either. Can be front suspension worn bushings. Suspect sway bar links as one given frequency of posts here. For vibration on braking, I had specific experience with that on D3 W12. Thought it was maybe brake rotors, maybe tie rod ends, maybe... Turned out to the the infamous D body upper control arm bushings--the second time they were replaced in under 100K miles, with OE parts each time. 19.5K is early even for those--more like 35 or 40K as more common minimum. But, never say never with big heavy Audi wheels and rotors hung on a mid 90's A4 front arm design at its core.

Baloo588

Since he has low miles I am concern he has disk variance thickness of his rotors due to uneven deposit and that is hard to remove and will cause vibration. I would say the rotors needs to be replaced depending on what the dealer finds in regards to the disk thickness variance measurement or runout measurement. I had my dealer measure it on my 2016 Audi A7 when the rotors started to make noise and vibrate badly at around 9k miles and it was due to disk thickness variance and I got them replaced under warranty.

MP4.2+6.0

Agreed, possible/more likely it is something like that given the modest miles. Fortunately on a 3.0T, those should be the less expensive std. construction rotors even if not warranty covered.

Puzz1

Thanks for he comments and advice. I will get it checked out.

tenspeed

These sites explain what's happening and how to deal with it in the future.

Friction pad material transferred unevenly to the surface of the disc link
-Warped- Brake Disc and Other Myths

How to bed in brake pads

Jack88

For the record, even at 72k miles when I sold mine, on it's second set of rotors since around 30k miles, I never had even a tiny shimmy from braking. I don't know if those deposits are related to driving habits, climate, or method of storage.