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Brake rotors have black/blueish dots and marks - Perfectly normal?

These are the rears rotor and after a drive, so it’s not jut a surface rust type of thing. Were changed about 2000KM ago along with the brake pads.

Is it normal? Or what is it? I thought a good rotor surface’s should be clean and shiny after a drive.

Does not look normal to me. Front rotors shiny? Wondering if the rears are not getting full force.

My front where changed about 1000km after the rear. Pads and rotors aswell

Here are my front rotors closeup: https://i.imgur.com/zhPQoQV.jpg Seems like it’s starting to do the same thing?

Here is another close up of the rear: https://i.imgur.com/3Z8LYBw.jpg

Looks like rust pits in the rotors, how cheap were they?

The rear are Centric C-TEK and the fronts are CENTRIC Hi carbon coated hats

The blue might vary with the composition of the rotors. The photos
Are truck:
normal surface rust after two day, it is exposed to salt air.
truck after driving, bluish rotor
car after driving, less blue
Truck—original pads/rotors 55000 miles
Car, OEM pads 4000 miles ,rotors turned at time of pad replacement
To my layperson impression, your rear pads are not making full contact or pads are contaminated
image image

I would have to say the cast iron used in these rotors is a bit more porous than it should be. I have tried Centric rotors in the past and found them lacking. I won’t buy them again.

That said, they look functional, drive on.

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Hmm ok I’ll keep that in mind next time.

Yeah I don’t get any pulsing or shaking. I hope tho they will still last haha. Will wreck the look of my car this summer with my nice looking rims, oh well.

Suppose you could hit them with some brake cleaner.

The C-Tek line of parts is a budget line aimed at used car lots, shops that advertise cheap brake jobs, and the DIY crowd that is more interested in price than quality. For example, a C-Tek wheel bearing/hub assembly will have an expected life of about 30,000 miles, where the Centric part will last as long as OEM parts. This comes to me direct from a Centric product engineer.

I’ve had good luck with Centric coated rotors. I wouldn’t buy a C-Tek rotor.

Ah, I thought Centric stuff was like OEM/OE without the name tag.

Yeah the front are the electro plated hats or something in black. I guess I’ll see how they go.

I also got the Centric Metallic premium pads. Any thoughts on those?

I think they will be dirty pads. Dust up your wheels quite a bit. Metallics are generally dirtier than ceramic pads, in my experience. Some worse than others, of course. They should stop just fine and last quite a long time, though.

Centric, like many other suppliers, have more than one level of product. Moog has their premium stuff and also sells a budget line called Quick Steer. AC Delco has their Professional line and their Advantage line. Gates sells their quality belts and also the Roadmax economy belts. And so on.

Centric Posi-Quiet brake pads have proven to me to be a quality product.

That’s not to say I haven’t ever used the C-tek pads and rotors on a customer’s car. I just don’t warranty them against noise and dust and offer a shorter warranty.

I wanted to get ceramic but I kept reading that initial cold bite isn’t as good and for performance or aggressive driving and winter overall a mettalic pad is better?

Is the cold bite THAT noticeable? I admit having less dust would be a plus.

No experience w/that brand of rotors, but the ones on my Corolla front wheels (original to this 27 year old car) are more shiny and less pitted than yours. Rears on the Corolla are drums so can’t compare to those. I expect that you aren’t doing as much hard braking as is required to buff-shine the rotors, esp true for the rears which generally apply less force between the pads and the rotor than the fronts; i.e. nothing to be concerned about as long as braking performance is good. If you ever had occasion for the car to sit a fairly long period of time (weeks or months) unused the rotors could have rusted then too, after which the pitting will show up more, like this.

I have had a couple of sets of ceramics when I lived where it got cold. Really didn’t notice any cold stop issues. There is probably more difference brand to brand than metallic to ceramic. Ceramics are definitely cleaner.