Sesquipedalian

Over torquing of the lug nuts at the factory is my theory. Just plain "factory defective" is another. This was a new car.

rxbruner

Good news. The Mercedes dealership was awesome and put on new rotors. The brakes are working great now. Cheers

They gave me instructions for bedding in the brakes so I did that too.

50pascals

For clarification, the rotors were probably not "warped" in the sense that the centerline of the rotor disc oscillated axially.

More likely it was what is called "pad rust."

When the car sits for a while the rotor face corrodes. But under the pad and at the margins it corrodes at different rates.

So you end up with an uneven surface.

I have been able to fix this with careful use of a random orbit or belt sander while spinning the rotors on a tire machine - but this is not recommended.

Usually a light skim with a brake lathe will do it. If a car has sat for longer than 6 to 9 months outdoors, anywhere outside of the Southwest states, it will have pad rust.

Anyone at the dealership that has even a passing experience with cars knows this. But they choose to roll the dice on the cost of the rotors, hoping you won't come back.

With any factory buyback vehicle, or any of the TDI's that were on "Stop Sale" replacing or turning the rotors should be mandatory, but usually isn't.

bpd

Dealer did good for you.

FirstAudi2012

Regarding 'winter' tires ... my 2012 A6 3.0T Prestige is the best vehicle I have ever driven in the snow. I got a great deal on a second set of stock rims thinking I would buy full winter tires and never did. You don't need to - the stock Conti All Seasons were very good in the snow and ice and the quattro system is ludicrously good. If you have Summer tires then I would definitely look for a set of stock wheels and either A/S or winter tires. Winter tires would be the ultimate of course and if you REALLY want to totally ignore the ice and snow and it would be very fun driving with full winters. The only problem becomes all the others on the road slipping and sliding around you. The downside is winters are softer and if the weather is warm or you want to run at higher speeds the winters don't have the same structural strength in the tire. ie. your handling characteristics are degraded. Note: I like to drive fast. If cost isn't an option check out the winter packages Audi offers. I think they had Pirelli Sottozero winter tires.

I have since moved to Memphis and no longer need my extra rims. I have a full set of 2014 stock rims and tires in the garage. If you can get them transported back to MN you can have em cheap ....

amtt81

I bought a '16 3.0 with 22k miles. After 8k miles the same thing is happening to me. I am surprised because I havent had this on other cars in such a short time. It been too long for me to go back to the dealer though.

I am looking for recommendations on upgraded rotors pads.

bpd

For some reason these cars develop this condition quite a lot, at least reported to forums. Something to try out is the Powerstop brake kit that comes with rotors and pads. Im assuming you have the 356mm rotors. Rockauto has the kit for $200 with Z23 pads.
The only thing that I can vouch for is the Z26 pads I got for my S6. Im very happy with them for the low dusting and good braking. Z23 pads use the same pad compound, just different backing plate. You can get more info at the Powerstop website. Im sure others will chime in with other recommendations. A friend of mine also got the Z26 pads for his S6 and he is just as happy as I'am.