superswiss

Couple of points here. First off, your dealer is supposed to do a multipoint inspection when your car is in for service and give you a printed report at the end, which among other things will show the remaining pad thickness. It's even a question on the service survey that you might get from Audi. You should ding them for not doing that. You pay for it. Or maybe talk to your SA and ask why they didn't do one and tell you the remaining pad thickness.

As far as brake wear goes, that pretty much entirely depends on how you drive and a big factor is the weight of the car. This is a 4000 lbs car. It will eat brakes and tires if you drive it like it's meant to be. An S3 is something like 500 lbs lighter. That's a huge weight difference that you will notice in brake and tire wear. If you drive mostly highway with very little braking, then yes, you could get a lot of miles out of a set of pads, but if you drive lets say in a more spirited fashion and actually use those brakes, then be prepared to replace them relatively early. 20k miles is not unusual if the brakes are used often and on the harder side. I got around 24k miles out of my first set of pads with my '13 RS5. Those first 24k miles included 4000 miles in Europe with lots of high-speed Autobahn braking. I switched to aftermarket pads after that and got around 35k miles out of them. Still regular and frequent fairly hard canyon driving, but the aftermarket rotors and pads are a bit harder than the OEM pads. Pads are always a trade off. Softer pads are more friendly for daily driving and produce less noise, but they wear out quicker among other things.

SolventSolution

Yep, my 10k service said the pads were fine but I have noticed a lip forming in the rotors. We’ll see how long she holds out. Rear rotors are more worn than the front.

J. Patterson

Yes, one further note that rear brakes on modern cars often wear quicker than on previous models due to the increasingly sophisticated electronic stability controls our cars now have. https://www.bendix.com.au/bendix-new...bility-control
i have seen Porsches at track events ( especially Caymans) that overheated the rear brakes because the stability control (PASM) applies rear brakes individually to help the car to turn. The red calipers often turn dark colored from repeated heating. ( if you see a Porsche with purplish rear calipers you’ll know it has seen considerable track time.)
BTW this is why I love Audi’s Sport Differential. It helps the car turn by changing the gear ratios between the inner and outer wheels. Thus engine power is greater to the outer wheel rather than applying braking to the inner.

JD15

Yes, I imagine most would not be happy with brakes that constantly squeal until they are brought up to temperature.

WasSD18S5CAB

Agreed. I needed rear pads and rotors at 25K. I suspect that those anticipating much longer than that for the rears are due for an unpleasant surprise. I'm at 33k and haven't had to do the fronts yet but am expecting I'll need to before 40k. I would not consider my driving style to be atypically hard on the brakes.

scoopman

An update. So the sensor was not wrong:

-- I have 20800 mi and my fronts are at 5, rears at 3 and need changin'
-- heisnuts@ is correct that they change the pads and rotors, and sensor (I think there's a sep one for the rear, or for each wheel, not sure) and since its the rear, the parking brake needs to be moved
-- Total from the dealer is $980 (ouch!) and the rotors are not in stock so this is a 2-day job
-- The dealer did provide the info on pad wear at my 20k service, it was on another page from the brake fluid change, I didn't notice it. my rears were at 4 at the 19,7xxx service

As far as my driving habits / style, I clearly do enjoy my car and I'm frequently in Bay Area commuting traffic where I do use DAP (but not Traffic Assist that much, I find its style of driving unnatural). I do have the sport dif, but that doesn't use rear brakes to rotate the car, so not sure why the rears are wearing out first. I decided to go with the stock pads / rotors as I'm not sure I want a harder compound, and also didn't want to replace all 4 wheels-worth of them.

superswiss

As far as I know, ACC uses the rear brakes first for moderately slowing down the car to avoid weight transfer to the front, so a lot of commuter traffic will wear down the rears faster.

SolventSolution

Yes, my last two VW's did the same thing. They blew through rear brakes at twice the rate as the fronts. I remember reading that it was to prevent nose dive of the car and that it was safer if a pedestrian was hit. I always wondered if that was the case why they didn't start making the rear brakes bigger...

Nikon1

ADP!

(Added Dealer Profit)

I believe almost all cars have proportioning valves after the master cylinder to “favor” the rear brakes for the reason you listed as well as minimizing steering control loss.

Mine goes in for the 12 month oil / filter & service in about 2 weeks. I’ll ask them to check the brake pads and rotors.

— John

MH62

Yes, my independant mechanic says rear brake wear out is now the norm on most cars, even prior to self braking cruise control. Cars used to be front brake biased because there's nothing worst than rear wheel lockups but now with help from computers, brake biased has shifted to the rear for passengers comfort and computers do their thing to avoid lockups and spins under heavy braking. Now why haven't they increased the rear brake components, we can only speculate.