[pmsteinm]

When I took delivery of my 2023 M5 I saw rust coating all steel areas of the rotor aside from the swept area. Aren't they zinc coated to prevent that? My wife's 2019 X5 rotors are rust free, as are the ones on my 2009 CTS-V. I know the car sat outside in Germany for a while.

And no I should not have gotten CCBs because I don't want to be on the hook for $25-40k for new rotors in 10 years or whatever.

[ResIpsaLoquitur]

Originally Posted by pmsteinm

When I took delivery of my 2023 M5 I saw rust coating all steel areas of the rotor aside from the swept area. Aren't they zinc coated to prevent that? My wife's 2019 X5 rotors are rust free, as are the ones on my 2009 CTS-V. I know the car sat outside in Germany for a while.

And no I should not have gotten CCBs because I don't want to be on the hook for $25-40k for new rotors in 10 years or whatever.

Mine will rust in the same places, typically after a car wash, but will go back to showing no rust within a day at most. Is your rust persisting?

[pmsteinm]

Not sure yet. Only 60 miles of driving so far, in the rain. I assume the swept area will clear up, but see the vanes:

[ResIpsaLoquitur]

Originally Posted by pmsteinm

Not sure yet. Only 60 miles of driving so far, in the rain. I assume the swept area will clear up, but see the vanes:

I do get this, too, but mine clears very quickly. There might be some kind of deposit on there if it’s not clearing quickly which should definitely be addressed by your dealer on such a new car. Document the issue in case you need to go that route so they won’t confuse it with swept area rust and tell you it’s normal and it will go away soon: i.e., snap a photo every X number of miles or something along those lines. There’s nothing more frustrating than getting to the dealer and they think they know more than you when you definitely know there is a problem.

[shawnhayes]

I’m afraid this can’t be avoided most of the time. Likely that you’ve had an exposure to salt or something sometime.

Unlikely that BMW will recognize this as “a problem”. Rusty metal brakes is par for the course. They are wear items.

Shawn

[pmsteinm]

Yeah I'm sure it got salt. There was a freezing rain warning in Bremerhaven around the time my car was there.

I notice some of the rust wiped off with a damp paper towel. I'll drive it and complain at the 1200mi service.

[pmsteinm]

The swept area is getting better, and the cross drilled holes are filling with dust. But the cooling vanes still aren't any different and I don't see how they can be. I guess they don't zinc coat the rotors? That seems really lame.

[pbonsalb]

In time, some brake dust and dirt should get in there that will make the fresh light brown rust turn dark brown, which may be a little less noticeable.

[pmsteinm]

Originally Posted by pbonsalb

In time, some brake dust and dirt should get in there that will make the fresh light brown rust turn dark brown, which may be a little less noticeable.

Do yours have rust there (assuming you don't have CCB)? I really would expect a zinc coating there to prevent the rust in the 1st place.

[pbonsalb]

Yes, my original 5 year old rotors are rusting at the inner and outer circumference of the rotor face that is untouched by the pads, on the outer edges of the vented rotors and in the drilled holes through the veins in the vented rotors.

The photo is not a very good one but you should be able to see much darker rust. Sometimes if the car is outside and not driven for a while and it rains, I will get surface rust that is brighter like the OP’s rust, but it goes away. A picture of one of my new rotors still in the bag. I’ll change them when the drilled holes start closing up with rust or the rotors are worn beyond the factory spec. I bought a set on sale recently.

[ResIpsaLoquitur]

Originally Posted by pmsteinm

The swept area is getting better, and the cross drilled holes are filling with dust. But the cooling vanes still aren't any different and I don't see how they can be. I guess they don't zinc coat the rotors? That seems really lame.
Attachment 3152109

I still do not think this is normal for such a new car. Surface rust over the swept area, yes. But not this. Even my previous M5 with the same rotors, I didn’t have this after ~29K miles and ~31 months of ownership.

[shawnhayes]

Originally Posted by ResIpsaLoquitur

I still do not think this is normal for such a new car. Surface rust over the swept area, yes. But not this. Even my previous M5 with the same rotors, I didn’t have this after ~29K miles and ~31 months of ownership.

Depends on use. You get these **ckers hot and they rust like crazy. ALL of my metal rotors have rusted like this. I’ll try to grab a pic of my old 2018 rotor I’m keeping around.

Shawn

[Maverik259]

Originally Posted by pmsteinm

When I took delivery of my 2023 M5 I saw rust coating all steel areas of the rotor aside from the swept area. Aren't they zinc coated to prevent that? My wife's 2019 X5 rotors are rust free, as are the ones on my 2009 CTS-V. I know the car sat outside in Germany for a while.

And no I should not have gotten CCBs because I don't want to be on the hook for $25-40k for new rotors in 10 years or whatever.

You’re thinking Porsche. You can easily source the rotors for under $15k. Hell you can do the conversion for like $15k on eBay. Do you really plan to daily drive and keep this thing for 10 years? That seems like a stretch. And if so just sell it once they’re up for replacement. Lol.

[shawnhayes]

Originally Posted by Maverik259

You’re thinking Porsche. You can easily source the rotors for under $15k. Hell you can do the conversion for like $15k on eBay. Do you really plan to daily drive and keep this thing for 10 years? That seems like a stretch. And if so just sell it once they’re up for replacement. Lol.

$15 k is still A LOT for brakes. I know some people have money out the wazooo, but that's a lot.

Shawn

[pmsteinm]

Originally Posted by Maverik259

You’re thinking Porsche. You can easily source the rotors for under $15k. Hell you can do the conversion for like $15k on eBay. Do you really plan to daily drive and keep this thing for 10 years? That seems like a stretch. And if so just sell it once they’re up for replacement. Lol.

I do plan to daily drive it for that long or perhaps more if it holds up well. I've been reading the F10 forum as well to get an idea on longer term issues. But in 10 years I wonder if anything "better" would even be available. Electric cars hold no interest for me at all. And in any event it will take 10+ years to convince my wife that I "need" a new car.

[shawnhayes]

Rusty rotors. Off my 2018. They looked like this immediately after my first track event and until I took them off the car.

Shawn

[pbonsalb]

I think the dark colored rust looks better than the fresh orange colored rust. My rotors have dark colored rust like yours. They are original and 5 years old with 45k miles. I sometimes get fresh colored rust if I drive in the rain and then park the car and don’t drive it for a week, but the orange color never stays long.

If I had really bad OCD, maybe I would pay $15k for a CCB conversion or buy a different car, but I don’t have OCD. Probably the squeaky brakes would bother me more than the rust if I had OCD. CCB fix the squeaks as well. They are probably the best choice for someone with OCD — well worth the option price, which is less than the conversion price.

[pmsteinm]

Mine are starting to get darker. I'm more annoyed that they don't seem to coat the rotors anymore. I saw some posts on the F10 forum complaining too compared to the E60. The Brembos on my V are fine even after a few track events. And the X5's are fine but they have never gotten hot.

If they are behaving as expected than so be it.

Now that I've got 380 miles on the car the brakes feel a lot better.

[pbonsalb]

Supposedly BMW updated the brake pad so the new cars don’t squeak or squeak less. Maybe you will be spared that and have to suffer only the rust. Let the car get dirty and brake dust accumulate on the wheels and you won’t notice the rust as much.