Can I get your opinions on my front rotors

[Jim2000]

Based on my experience, I completely agree with Carguyshu and a few others that have posted. There are two issues that some owners are experiencing. The first is uneven pad deposits on CT4V-BW rotors. The second is dealer service departments that are providing based information to owners. They can't really tell a customer that they have to go brake hard to get rid of deposits, then re-bed the brakes, probably with new pads. So their solution is to install new rotors since that approach does fix the problem. Of course, this is an expensive fix.

We should not be getting uneven pad deposits on these cars. I have never owned a sports car with this kind of problem. This is the weak link in our cars and it is unacceptable.

 

[PL69]

I just came back from 2 days of intense track days with my 4BW and no problem what's so ever. This is my 3rd track day and pads are still good for one or two days (OEM). I am very hard on the brakes.

 

[pkincy]

Yeah, I probably won’t be doing this full job at home. I like to DIY things when I can but not sure I want to mess around with brakes.

What’s the recommended bedding procedure for these brakes?

Someone else may have commented on this already as I am only on page 3 of this thread but changing pads only on our cars is ridiculously easy. I am old and lazy and I do it in two sessions. One for the fronts and one the next day for the rears, but it is less than 2 hours at my near 80 year old speed for each session and that includes starting with 4 wheels on the ground and finishing each session with 4 wheels on the ground. And normally I will clean the wheels and re ceramic coat them anytime I change pads to make cleaning them easier.

 

[Neveready]

On a BMW M2, my computer said I had 58k miles left on the front brakes when I sold the car with 14k miles on it. No vibrations. Why are people having vibration problems on the Blackwings with less than 10k miles?

The f87 M2, I am assuming you had this model, weighs 3300lbs, the 5 is over 4100lbs. 800lb can make a huge difference regardless of the size of the rotors, it's just going to eat rotors, pads and tires quicker.

Also, these cars can gain speed alot quicker than many other sports cars and so you use more of these commodities.

But I agree, 10k mi on rotors is an extremely short lifespan. I'm pretty confident that it's uneven wear, and there is plenty of surface steel left on the iron rotor.

I'm wondering if washing the car and not going for a drive to get off the deposits could be causing uneven wear. Or is the problem the brakes are so powerful they aren't fully being applied on the street...Thoughts?

perhaps a less aggressive pad such as a ceramic pad like @pkincy mentioned may be beneficial for street use and they may wear more evenly. Once you have clean rotors, you can keep the OE pads for track use or put them back on to remove the deposits if ceramic pads left uneven wear on the rotors.

 

[pkincy]

If you don't track the car then you don't need the stock brake pads. You can get a set of the Power Stop Z26 series ceramic pads for $80. I ran these in the winter and the stopping power on the street feels identical to the factory pads.

And if you don't track the car this is the way to go particularly if you don't like brake dust. It is also the way the Camaro and Corvette C7Z06 go if they aren't tracking their cars. I resisted on my Z06 as I didn't want to put $80 worth of pads on my $110,000 car when it was new, so used the Carbotech 1521s which were $550 instead. But I did use the PS Z26s on my ATS-V and soon realized that they were as good after using both for 3-4 years. So the CT4-V BW has the Z26s on it now.

 

[Carguyshu]

On a BMW M2, my computer said I had 58k miles left on the front brakes when I sold the car with 14k miles on it. No vibrations. Why are people having vibration problems on the Blackwings with less than 10k miles?

OEM m2 brakes are garbage. Every single person I know that tracks theirs tosses them as they overheat easily and come apart in chunks. They literally fall apart. I guarantee I could toast them in under 300 miles. The OEM brakes on the bw aren’t even in the same universe. It’s laughable how much better they are.

My dad has over 125k on his Silverado and hasn’t had to replace any pads. So they must be the best in the world right? Or maybe he just drives all the time on the highway….

 

[Carguyshu]

The f87 M2, I am assuming you had this model, weighs 3300lbs, the 5 is over 4100lbs. 800lb can make a huge difference regardless of the size of the rotors, it's just going to eat rotors, pads and tires quicker.

Also, these cars can gain speed alot quicker than many other sports cars and so you use more of these commodities.

But I agree, 10k mi on rotors is an extremely short lifespan. I'm pretty confident that it's uneven wear, and there is plenty of surface steel left on the iron rotor.

I'm wondering if washing the car and not going for a drive to get off the deposits could be causing uneven wear. Or is the problem the brakes are so powerful they aren't fully being applied on the street...Thoughts?

perhaps a less aggressive pad such as a ceramic pad like @pkincy mentioned may be beneficial for street use and they may wear more evenly. Once you have clean rotors, you can keep the OE pads for track use or put them back on to remove the deposits if ceramic pads left uneven wear on the rotors.

Bad idea as you’ll have a different compound burnished on the rotors that may be incompatible with the other brakes. Carbotech makes pads that are all compatible to fix this problem (meaning you can switch from low dust street to track pads & back bc they’re all compatible compounds without having to reburnish or resurface rotors) but switching to a non OEM pad has a lot of downsides when looking at all the programming in all the electromechanical systems that are anticipating the OEM compound. This isn’t even taking into consideration the car is brake by wire with no physical link to the pedal. All that brake programming is optimized (including potential overheat messages) for the OEM compound.

 

[Jim2000]

OEM m2 brakes are garbage. Every single person I know that tracks theirs tosses them as they overheat easily and come apart in chunks. They literally fall apart. I guarantee I could toast them in under 300 miles. The OEM brakes on the bw aren’t even in the same universe. It’s laughable how much better they are.

My dad has over 125k on his Silverado and hasn’t had to replace any pads. So they must be the best in the world right? Or maybe he just drives all the time on the highway….

Perhaps you are correct if you track the car which most people do not. We should have brakes on these cars that will last a reasonable amount of time and there should be a brake upgrade for people who track the car. This would give us the best of both worlds.

 

[Neveready]

Bad idea as you’ll have a different compound burnished on the rotors that may be incompatible with the other brakes. Carbotech makes pads that are all compatible to fix this problem (meaning you can switch from low dust street to track pads & back bc they’re all compatible compounds without having to reburnish or resurface rotors) but switching to a non OEM pad has a lot of downsides when looking at all the programming in all the electromechanical systems that are anticipating the OEM compound. This isn’t even taking into consideration the car is brake by wire with no physical link to the pedal. All that brake programming is optimized (including potential overheat messages) for the OEM compound.

It doesn't have to be a ceramic pad, but if you say Carbotech has an aftermarket solution then essentially it's the same concept of what others have said about using a track pad for a burn in procedure or to go out to the track and fully utilize the brakes to get an even surface.

Regardless, the surface of the OPs rotors are uneven. If you use a more aggressive pad that you do a burn in procedure with, it will transfer a smooth layer and even out the surface which is the solution to uneven wear.

If it was my car, I would just do a very aggressive burn in procedure with the old 4mm pads, once those rotors are even and smooth, I'd put a new set of OE pads on and do another burn in procedure.

 

[poor-sha]

I found a DIY shop in Austin where you can rent a lift and you can also pay extra to have someone show you what to do, so I’ll prob do that the first time around

That’s great. Make sure you disconnect the battery before you mess with the brakes.

 

[Carguyshu]

Perhaps you are correct if you track the car which most people do not. We should have brakes on these cars that will last a reasonable amount of time and there should be a brake upgrade for people who track the car. This would give us the best of both worlds.

Buy the carbon ceramics if you’re not going to track. The rotors will last the life of the car. If you buy the track version of a car expect to get track components.

 

[strohw]

That’s great. Make sure you disconnect the battery before you mess with the brakes.

I see people mentioning that the car actuates the brakes during that process it performs when you step near it with the key. But I tested this when I changed my brake pads and it wouldn't do it for me. I walked up to and away from the car multiple times, locked and unlocked the car but it wouldn't do it.

 

[jodakid69]

I found a DIY shop in Austin where you can rent a lift and you can also pay extra to have someone show you what to do, so I’ll prob do that the first time around

I need to find one of these shops in the Philadelphia area.

 

[jodakid69]

I attached a video provided by the dealer tech of my front brake change, sorry for the bad resolution, The brakes had 5 track days and 5700 miles on them. It seems that the rotor thickness is 33.4 LF and 32.5 LF. The tech said that the wear sensors we almost at the wear point.

The new pads are EBC EC11. They do not allow the wear sensors to be installed, so the wear sensors were tie wrapped off. I will be inspecting the brakes before every track session. Therefore, the lack of a wear sensor is not an issue for my use.

 

[ukcats12]

I found a DIY shop in Austin where you can rent a lift and you can also pay extra to have someone show you what to do, so I’ll prob do that the first time around

This is actually a very cool concept. I'd love to do my own work, but I'm hesitant to screw anything up on such an expensive performance car. Having the ability to have a chaperone of sorts while you get familiar with things is pretty cool.

 

[poor-sha]

I see people mentioning that the car actuates the brakes during that process it performs when you step near it with the key. But I tested this when I changed my brake pads and it wouldn't do it for me. I walked up to and away from the car multiple times, locked and unlocked the car but it wouldn't do it.

It *could* actuate the brakes. I don't know if the car has to go to sleep and then wake up on key approach. I don't know if there is some sort of drop in pressure in the hydraulics that would need to happen. The first time I swapped pads on my C8 I didn't know to disconnect the battery and didn't have an issue. However, there have been enough cases of folks not disconnecting the battery and having the system bleed out that I wouldn't risk it.

 

[Seth]

Ok so now I'm in a weird situation. I finally got my front rotors and pads replaced. The shop I went with told me they were ordering OEM rotors but "accidentally" ordered GiroDisc and put those on. Is there any reason I should NOT want the GiroDisc on my car? I realize they are less expensive and I need to figure that part out with the mechanic.

 

[rdollie]

Which GiroDiscs? Can you share the mfg part #? Someone else just shared a list of compatible pads including Girodiscs here: KNSBrakes | Products | <!-- -->2022 Cadillac CT5-V Blackwing - Iron Discs

 

[Matt27]

Ok so now I'm in a weird situation. I finally got my front rotors and pads replaced. The shop I went with told me they were ordering OEM rotors but "accidentally" ordered GiroDisc and put those on. Is there any reason I should NOT want the GiroDisc on my car? I realize they are less expensive and I need to figure that part out with the mechanic.

Feels like general consensus would be that it's an upgrade though admittedly I've never run them on one of my cars. I was planning to replace the OEs with them.

The upside is you can just buy the replacement rings moving forward so it should get much cheaper for future sets. Know they're commonly used in BMW/Porsche land and generally well regarded, but I'll defer to others for any first-hand experience.

 

[Jim2000]

I recently participated in a Cadillac V-Club Tech talk. It is my recollection that Brembo stated that, "Cadillac Blackwing Metal Rotors should NOT be resurfaced, they must be replaced". I will hunt for that information.

The rotors on the ATS-V could be resurfaced and they had Brembo pads.