[keylime503]

I have a little over 18,000 miles on my F32, and iDrive is telling me my rear brake pads are due in 900 miles (front brake pads not due for 24,000 miles). Definitely would consider myself an aggressive driver and have done one HPDE on these stock brake pads. I have also started to notice some squealing sounds from the brakes when I'm coming to a stop, and even some light fading of the brake pedal, so all the signs of brake pad wear are there. Today I took some pictures of the pads through my wheels (attached) and I'm not sure what to make of the rear pads. They look like the same overall thickness as the front pads, but a couple mm of thickness closest to the brake discs look like grinded up metal. For what it's worth, the rear brake discs feel smooth and look the same as the front brake discs. Looking for some guidance on if this is normal and if they need to be replaced or not. First BMW, so sorry for the noob question. My last car never looked like this at least that I noticed. Thanks!

[msmiles]

Leading and trailing edge of the pad. Remember that your front brakes are at "9 o'clock" relative to the wheel and your rears are at the 4 o'clock. If you look at the bottom edge of the fronts, you would see the same thing. Look at the inside edge (closest to the wheel hub), you can see the rear pads are further worn.

[RoundelM3]

There was some kind of software update recently that caused this pad wear message to appear prematurely. You might want to check with your dealership about that.

[Polo08816]

Originally Posted by roundel335

There was some kind of software update recently that caused this pad wear message to appear prematurely. You might want to check with your dealership about that.

If the OP checks up on his pads frequency, could he get away with not attaching the brake pad wear sensors to the brake pads?

(I haven't tried it yet.)

[RoundelM3]

Originally Posted by Polo08816

If the OP checks up on his pads frequency, could he get away with not attaching the brake pad wear sensors to the brake pads?

(I haven't tried it yet.)

Nope...you do that, and BMW service will raise hell about it. He should just check whether the software update applies to his car; otherwise, it could be something else like a faulty wear sensor.

[Polo08816]

Originally Posted by roundel335

Nope...you do that, and BMW service will raise hell about it. He should just check whether the software update applies to his car; otherwise, it could be something else like a faulty wear sensor.

I have 59k miles on the odometer, BMW maintenance program is already done.

Doing this would not surprise me for those that track often and are, therefore, changing pads often.

[RoundelM3]

Originally Posted by Polo08816

I have 59k miles on the odometer, BMW maintenance program is already done.

Doing this would not surprise me for those that track often and are, therefore, changing pads often.

To each their own; but thinking about it, the computer can give you a warning such as the OP is seeing, but unless the wear sensors are contacting the actual brake disc surface, it's more than likely the software glitch giving this warning. Removing the pad sensors won't affect what the computer tells you. The sensors are not "gradual", but more of an on-off situation.

[Polo08816]

Originally Posted by roundel335

To each their own; but thinking about it, the computer can give you a warning such as the OP is seeing, but unless the wear sensors are contacting the actual brake disc surface, it's more than likely the software glitch giving this warning. Removing the pad sensors won't affect what the computer tells you. The sensors are not "gradual", but more of an on-off situation.

I agree. The brake pad wear sensors seem to be more of an "open" or "closed" circuit design.

I'm wondering whether resetting the Brake pad CBS % would help in the OP's case.

[RoundelM3]

Originally Posted by Polo08816

I agree. The brake pad wear sensors seem to be more of an "open" or "closed" circuit design.

I'm wondering whether resetting the Brake pad CBS % would help in the OP's case.

Good question...I seem to remember a way to reset service intervals, although I'm not sure if it was with E-Sys or with Carly for BMW (which can read and clear codes and possibly service intervals too). I do remember having my 2013 335i's software updated due to a TSB for that problem with the rear brake pad service interval showing up too soon. Was within the last year as I recall.

[Vitoco]

Don´t forget to look at the INNER pad, probably more worn! It´s decieving when you just look at the outer, visible, pads.

[floydarogers]

Originally Posted by keylime503

I have a little over 18,000 miles on my F32, and iDrive is telling me my rear brake pads are due in 900 miles (front brake pads not due for 24,000 miles)....

The rears on BMWs since E9x days wear faster than the fronts; BMW has tuned in some "rear brakes grab 1st" for anti-dive, and also it uses the rears for traction control/electronic limited slip differential. What you have is probably normal. You might consider getting some higher-performance pads for track-day use to save your street pads; not really a worry either way.

I'm pretty sure that the brake wear sensors have TWO wires (they get worn off and no longer are shorted when they contact the rotor). The first one is near the top of the pad and is used to determine a wear rate that the computer uses to predict miles to replacement. The second tells you when you have only a bit left and must replace the pads NOW.