Rusted PSCB brakes

[Johan Meert]

Go run that car like it's meant to be. Hard acceleration followed by hard braking to get past the point where the motors are doing all of the braking. Go have some fun and then check those rotors again.

This.
Before spending any money on this, do a few emergency brakes and take pictures before and after.

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[Jenner]

Your rotors are perfectly fine! (if its just "rust" we are talking about)

According to Porsche the PSCB should last 100k on an ICE car that has to use it's brakes 100% of the time. They should last the lifetime of the Taycan since it does so much braking via regen in advance of using the mechanical brakes. Unless your Taycan has been tracked hard for many many miles, anyone trying to sell you brake rotors at 30k miles is trying to rob you. Don't fall for it!

Those on here saying things like " doesn't look fully run in. PSCB are usually mirror finish when fully run in" or "my discs are shining like new" or " They are just not run in, and that can be cleaned" are wrong and/or are spreading misinformation.

Here is what PSCBs look like with too much slow driving/no heavy braking and/or haven't been bedded in properly:

Here is what PSCB they look like after they have been used hard and bedded in properly. "Bedded in" means some of the brake pad is "stuck" to the rotor. You can see this with the blue/grey deposits on the rotor in the picture below:

If they are NOT blue/grey then you need to go out and get up to 60-80mph someplace safe and brake HARD down to ~25-30mph, but do NOT get into ABS braking and do NOT come to a full stop! Do this several times in a row allowing a period of cool down in between each hard stop. A quick google search will also provide more info on this technique.

But going back to point A to point B aka "around town driving" or lots of highway driving with infrequent use of the brakes will cause the deposits to be scrapped off over time as the pad deposits on the rotor when the brakes heat up and gets removed when the brakes are cold. So you may need to repeat this process again from time to time.

 

[escobarrr]

Im seeing a lot of pictures of the outside of the rotors, they are saying the rust is on the inside. Is there a easy way to see it without putting it on a bridge? Next week im gonna look at it with a local garage to see for myself how bad it is?

The thing in do know now is that i have to brake hard from time to time. I also have a Tesla model X and wich doesnt have pscb off course, so gonna do it with that one as well.

 

[Jenner]

Look at the name of these rotors "Porsche Surface Coated Brakes"
These rotors are normal cast iron brake rotors but they have add a 0.1mm coating of tungsten carbide on the rotor surface.
And only on the surface. The rest of the rotor is iron and will rust like any iron rotor would especially on the inside and other surfaces not touched by the brake pads.

Both of the pictures below of Porsche iron brakes showing rust on the vanes and at the hub is completely normal for cast iron rotors OR the iron parts of PSCB rotor and is completely HARMLESS. No need to worry about braking issues and absolutely no need to replace the rotors!

Google image search "Porsche rusted brake rotors" and you will see plenty of examples. It is normal on any car. Want to see it in real time just spray water on iron brake rotors from any car brand and they will rust up right away and is harmless and normal.

If you want rust free brake rotors you need PCCB (or any ceramic brake rotor on any brand) but even then the hub itself can still rust, just not the rotor:

 

[mystermykee]

Your rotors are perfectly fine!

According to Porsche the PSCB should last 100k on an ICE car that has to use it's brakes 100% of the time. They should last the lifetime of the Taycan since it does so much braking via regen in advance of using the mechanical brakes. Unless your Taycan has been tracked hard for many many miles, anyone trying to sell you brake rotors at 30k miles is trying to rob you. Don't fall for it!

Those on here saying things like " doesn't look fully run in. PSCB are usually mirror finish when fully run in" or "my discs are shining like new" or " They are just not run in, and that can be cleaned" are wrong and/or are spreading misinformation.

Here is what PSCBs look like with too much slow driving/no heavy braking and/or haven't been bedded in properly:

Here is what PSCB they look like after they have been used hard and bedded in properly. "Bedded in" means some of the brake pad is "stuck" to the rotor. You can see this with the blue/grey deposits on the rotor in the picture below:

If they are NOT blue/grey then you need to go out and get up to 60-80mph someplace safe and brake HARD down to ~25-30mph, but do NOT get into ABS braking and do NOT come to a full stop! Do this several times in a row allowing a period of cool down in between each hard stop. A quick google search will also provide more info on this technique.

But going back to point A to point B aka "around town driving" or lots of highway driving with infrequent use of the brakes will cause the deposits to be scrapped off over time as the pad deposits on the rotor when the brakes heat up and gets removed when the brakes are cold. So you may need to repeat this process again from time to time.

I was just about to refer this thread to your post about this! Excellent!

 

[Fantasmos]

Check this out

https://static.nhtsa.gov/odi/tsbs/2024/MC-11006857-0001.pdf

 

[Beattie]

Check this out

https://static.nhtsa.gov/odi/tsbs/2024/MC-11006857-0001.pdf

Interesting that it states if hotspots are found on the disc it isn’t a warranty claim.

 

[Fantasmos]

I read it that spots all by themselves are not an issue. Here are “mine”. I am still waiting two weeks to get the car from Porsche but that’s the photo the dealer sent me. I think it’s not something to be worried. I am waiting for the 111 test to extend my warranty so they won’t have any excuses to make if there’s an issue.

 

[Beattie]

I read it that spots all by themselves are not an issue. Here are “mine”. I am still waiting two weeks to get the car from Porsche but that’s the photo the dealer sent me. I think it’s not something to be worried. I am waiting for the 111 test to extend my warranty so they won’t have any excuses to make if there’s an issue.

Btw, nice wheels. I have them too. So I’m currently trying to get one of my rear discs done under warranty. The car was in for the brake recall last week and during the health check they found the inside of the rear discs had areas where the carbide coating had come off. Initially they said it was just wear and quoted me £3k to have both replaced. When I pushed them for evidence of the their disc they reluctantly sent me a photo and admitted the other disc was blemish free. So I have now pushed for a warranty claim. We will see.

 

[Fantasmos]

That’s not a hotspot but delamination of the cover. They should replace both disks under warranty imo.

 

[escobarrr]

Look at the name of these rotors "Porsche Surface Coated Brakes"
These rotors are normal cast iron brake rotors but they have add a 0.1mm coating of tungsten carbide on the rotor surface.
And only on the surface. The rest of the rotor is iron and will rust like any iron rotor would especially on the inside and other surfaces not touched by the brake pads.

Both of the pictures below of Porsche iron brakes showing rust on the vanes and at the hub is completely normal for cast iron rotors OR the iron parts of PSCB rotor and is completely HARMLESS. No need to worry about braking issues and absolutely no need to replace the rotors!

Google image search "Porsche rusted brake rotors" and you will see plenty of examples. It is normal on any car. Want to see it in real time just spray water on iron brake rotors from any car brand and they will rust up right away and is harmless and normal.

If you want rust free brake rotors you need PCCB (or any ceramic brake rotor on any brand) but even then the hub itself can still rust, just not the rotor:

It feels like i dont have any trouble with breaking, i havent seen any rust anywhere tho.
but i cant get my car through the inspection unless i get new brakes is what Porsche is saying.

but if i get you correctly it can be possible that the brakes are done after 45.000 km and 4 year because of rust. Is that right?

Btw, nice wheels. I have them too. So I’m currently trying to get one of my rear discs done under warranty. The car was in for the brake recall last week and during the health check they found the inside of the rear discs had areas where the carbide coating had come off. Initially they said it was just wear and quoted me £3k to have both replaced. When I pushed them for evidence of the their disc they reluctantly sent me a photo and admitted the other disc was blemish free. So I have now pushed for a warranty claim. We will see.

i was hoping for something that i can claim something at porsche since it is only one brake that is rusted. The other one is perfectly fine. Unfortunately my warrenty is finnished. So dont think i can do anything with that

i managed to get a picture of the “rusted” brake.

 

[Jenner]

These pictures do not show any abnormal rust (to my eyes). Rust is reddish/orange in color. Maybe there is a little in the internal cooling vanes but that is completely normal for iron rotors (which PSCB are based on).

Your picture showing the outside rotor face could be large build up of brake pad deposit on the inner part of the rotor as @Fantasmos already pointed out OR it could be tungsten carbide coating has been worn through. Remember this coating is only 100 microns thick! (or micrometers)!

The picture showing the inside of the rotor face appears to me that the tungsten carbide coating has been worn through or worn off and should have been replaced as defective while the vehicle was under warranty. This leads me to believe the coating is missing on the outside rotor face as well but I can't tell for sure from these pictures.

I am not sure why your Porsche service is calling it "rust" but it simply isn't BUT ignoring the the term rust based on these pictures there IS something wrong with your rotors.

It is NOT rust nor would the type of rust I pointed out in my post/pictures above fail inspection. It doesn't matter what they are calling it as long they are refusing to pass the car because the coating is worn off and it does look worn off from that inside rotor picture.

If you are out of warranty I am not sure your options at this point. aside from replacing the rotors yourself. I feel this should have been caught at a prior service or inspection and wasn't as a warranty defect and now you are stuck paying for it.

Can you run your finger over those areas of the rotors and tell if it is raised up (brake pad deposits) or if it is depressed (material is missing)?

If the tungsten carbide coating is missing replace the rotors.

If it feels raised up then you could attempt to remove the pad deposits via mechanical means if you want to avoid the large replacement cost but I have no idea if this works on PSCB like it does on normal cast iron rotors so do this at your own risk! (but seems like you have nothing to lose anyways as the only other option is to replace the rotors):

Flex-Hone for rotors (can be found on Amazon as well):
https://www.brushresearch.com/brushes.php?c1=6


Edit
Found a clear picture of a PSCB rotor with a chunk of tungsten carbide coating missing:

 

[escobarrr]

Update!

Just had my porsche at the service center.
Inside of one of the brakes is completely rusted.
Paid about 5k euros to get the brakes in the back replaced. Getting the car back somewhere today.
They are going to put the rusted brake in the car so i can see it myself.

when i get it back i will share a picture here.
Still very confused about how it can be possible that the inside of 1 of the disks got rusted.
But think there is nothing i can do about it.

 

[escobarrr]

This is it. Indeed rusted.
how come. Still no idea

 

[Jenner]

The rust inside the hub is not as concerning as the multiple holes where PSCB material is completely missing and the "bubbling" of the tungsten coating around the rest of the rotor face.

It looks to me like the coating was worn through or worn off and then water possibly other chemicals got access to the material under the coating via the holes and then was additional subjected to extreme temps (ie hard braking).

Completely guessing here but either the tungsten coating was defective from the factory or this rotor was subject to some chemicals it didn't like.
I am thinking something along the lines of being parked at the beach with high exposure to salt water or possibly even being submersed in salt water/flooding for a time or less likely but plausible some aggressive car/wheel wash chemicals that did not agree with this rotor.

Since it was not noticed until the car was out of warranty the question of it being defective is out the window at this point.

The good news is it is off your car and no longer a safety issue for you but I would keep an eye on this rotor and make sure to check the back side of it that you can't see without getting under the car to inspect for this to happen again. Document everything about this rotor (and save this one) in case it happens to the 2nd one.

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