Steel brake wear question

[curehead]

Hi,

I have the steel brakes and have 19,000 km on the clock, including around 12 laps on the Nordschleife. My pad wear indicator in the idrive says I have 170,000km left on the front pads and 140,000km left on the rear pads. Is this normal? Just seems a bit too durable so to speak. And no, I don't drive like a grandma..

Cheers!

[JNoSol]

The stock pads will last 4-6 track weekends with proper brake management. The estimated brake replaced indicator is entered in manually by your service team. Not an accurate estimation based on abnormal driving style (tracking).

[CanAutM3]

Originally Posted by JNoSol

The stock pads will last 4-6 track weekends with proper brake management. The estimated brake replaced indicator is entered in manually by your service team. Not an accurate estimation based on abnormal driving style (tracking).

Are you sure about that?

My understanding is that the iDrive brake replacement interval indicator is based on an algorithm that uses driving conditions to estimate brake wear. It is just reset by the "service team" to a default value when new pads are installed.

I also seriously doubt that stock pads will last 8 to 12 track days. My stock pads were worn down to about 20% left after only 3 track days.

[JNoSol]

Originally Posted by CanAutM3

Are you sure about that?

My understanding is that the iDrive brake replacement interval indicator is based on an algorithm that uses driving conditions to estimate brake wear. It is just reset by the "service team" to a default value when new pads are installed.

I also seriously doubt that stock pads will last 8 to 12 track days. My stock pads were worn down to about 20% left after only 3 track days.

IDrive counts down how many times you use the brake, duration, speed, and force. It makes a guess of when you need pads next. When you take the car in for an oil change do measure the brakes to re-calibrate the true mm left on the pads.

I'm not 100% sure on the F8x stock pads. I based it off of the E92 M3 guys who have tracked their cars with stock pads. I have 80% brake left, 11k miles and 1 track weekend. I take it easy on the brakes the last lap to let the brakes cool off. Going to RPM next weekend with the stock pads and ATE TYP200 fluid. We get one free brake replacement so I haven't switched to track pads.

[CanAutM3]

Originally Posted by JNoSol

IDrive counts down how many times you use the brake, duration, speed, and force. It makes a guess of when you need pads next. When you take the car in for an oil change do measure the brakes to re-calibrate the true mm left on the pads.

That's interesting. I did not know that. On my E92, I could only reset the brake replacement mileage to a given default value, so I assumed it was the same on the F8X.

I'll make sure to check it out on my M4 .

[JNoSol]

Originally Posted by CanAutM3

That's interesting. I did not know that. On my E92, I could only reset the brake replacement mileage to a given default value, so I assumed it was the same on the F8X.

I'll make sure to check it out on my M4 .

That's what I've been told by 2 SAs now (not specific to the F8x, but all the other iDrive cars I've had). They could be b'sing to make me feel that they're doing more than just an oil change. Also, never let the pads wear down until the sensor goes off. The sensor has a wire, once it hits the wear limit the wire will short to indicate the urgent need to replace the brakes. You then need to replace the pads AND the sensor. The sensor can be re-used as long as you don't let it wear past the trip point.

[CanAutM3]

Originally Posted by JNoSol

That's what I've been told by 2 SAs now (not specific to the F8x, but all the other iDrive cars I've had). They could be b'sing to make me feel that they're doing more than just an oil change. Also, never let the pads wear down until the sensor goes off. The sensor has a wire, once it hits the wear limit the wire will short to indicate the urgent need to replace the brakes. You then need to replace the pads AND the sensor. The sensor can be re-used as long as you don't let it wear past the trip point.

Agreed. I don't even plug the sensors to the pads at all, I tie-wrap my them to the suspension. With the heat of track use, the sensors become brittle a crumble to pieces.

My understanding is that the brake pad replacement prediction in the iDrive and the pad wear sensors are not related. Both would trigger a similar alarm, but the signal comes from two distinct and indepenedent source.

[JNoSol]

Originally Posted by CanAutM3

Agreed. I don't even plug the sensors to the pads at all, I tie-wrap my them to the suspension. With the heat of track use, the sensors become brittle a crumble to pieces.

My understanding is that the brake pad replacement prediction in the iDrive and the pad wear sensors are not related. Both would trigger a similar alarm, but the signal comes from two distinct and indepenedent source.

Great tip on not plugging the sensor in. I've never thought about doing that, lol. Yes, iDrive is software estimation and the sensor is the hard indicator.