I pulled my car into the garage yesterday and as I locked the doors I noticed that the rear brake caliper wasn't looking right. I checked the other three calipers and the opposite rear was in the same condition. I had been driving a little aggressively on some curvy back roads and really hitting the throttle, though I don't think that should have damaged them.
Here's a poor partial image of my front brake caliper showing a nipple and part of the moniker. If I find the time today I'll pull the wheel off and get a better picture.
Early production 2018's had the S logo on the rears as well, but that changed sometime last year. Same on the S4's. Your pictures are normal for current production.
I went out and popped the tires off to get a better look. (Just what I wanted to do on a sub-freezing Sunday morning!).
Here's two photos of the back brake:
Compared to the front brake:
And, here's a little extra surprise I found on the garage floor after the wheels were back on! What does the "FE" stand for? "Freakin Extra" lol. So now I also have a wheel that's out of balance.
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