Hi everyone,
So long story short, got the car last christmas (dec 2020) from Germany at 19k Miles, have been driving it as my daily ever since, including with rear child seat (3y old son) on longer drives.
I put 18k miles on the car in the past year, I would like to mention I DRIVE the car hard and not cruise too often.
My average fuel consumption on the last 10k miles is: 13MPG (18.5L/100km)
I have been really happy with the CCB, first time having them on a car with the exception this major issue today. I noticed weaker than usual breaking on my vehicle yesterday so pulled over to visually check pads/discs and surprise both front rotors have failed and are damaged. (Partial spalling and Friction layer detachment I believe are the right terms)
It's shocking to me that both front rotors failed at pretty much the exact same time and at 38k MILES!!! I mean what are the odds of this happening on left and right rotor at the same time.
I have a few things that I cannot explain so maybe someone with more experience with CCB's can help and I can figure out exactly what happened.
Q1. Could this have been intentional and someone hit the discs as I did find my front left side, driver door and hood scratched pretty bad while at a ski resort this past weekend so quite a coincidence..
Q2. Can CCB rotos fail like this if pads were not replaced and they should have been? (visually they still have 1/3 or half life left on them). Will probably know the answer to this once I get the pads and rotors removed and replaced.
Q3. Could they have failed because I drove the car during winter and cold weather, maybe they did not like freeze-unfreeze weather and somehow they cracked as mountains and stones fall during winter.. (freeze-unfreeeze and water getting between cracks). I doubpt this is the case as I'm sure I am not the only person daily driving an M5 or CCB car during winter. Not to mention it's been a rather light winter so far and I have only done maybe 3k miles this entire season!
Q4. Would BMW or manufacturer (Brembo ) care this happened at < 40k Miles, car is not in warranty anymore or I'm sure this would have been probably resolved through them. Regardless I will go Monday or as soon as I can schedule a service check/inspection for discs and brakes.
Q5. Can anyone tell by the wear sensor on the rotors if this was a premature rotor failure, manufacturing flaw/defect or other? (I have not removed or weight the rotors, will do so but with a chunk missing from them not sure what that will tell me now). For me they appeared at least half life left on them, so maybe another 40-50k miles. I know they should be good for 100-150k depending on driving style.
I want to mention my rear rotors are fine and no issues so far with those.
Repair is pretty much the cost of a 2h car. ~$10k both front rotors. 5k each.
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Other than this MAJOR issue which is looking like it's going to set me back $10k, I was planning to get CCB's on my next car!
I love that wheels stay clean from break dust and the performance when pushing the car to it's limits, once they get warm braking is INSANE.
(Last image with the rotor is from 2-3k miles back. Also added 2 images with front pads that I found, I can take better ones after I take wheels off the car in a few days.)
After every drive I always do a cooldown run/slow drive around my block to cool down turbos and discs, I have been doing this on every car I had.
I'm very cautious and always manage the car with oil changes every 3-4k Miles, spark plugs ~(10k) and all services before time.
I know I can still drive the car but is there a risk other than lower efficient brakes? How safe is it? Obviously will not drive the car hard until I get the rotors and pads replaced.
Thank you guys for any help or insight you have on this issue and looking forward to some experts thoughts!