650i Gran Coupe Rear Brakes

[JNMiller]

It is looking like I need to replace the rear pads and likely rotors on my 650i. The iDrive shows all ok, but visual inspection shows the pads are super thin. It’s time. The left rear even sounds as if there is more than just the pad rubbing, almost metalic, but there is still brake pad remaining. Maybe something caught in it? Taking it in at 8am. Would order a drilling/slotted full set otherwise...if I could wait a few days.

Once this is done I think I’ll still explore the drilled/slotted option for the front and maybe rear too. Suggestions for pad and rotors on this car?

[Flying Ace]

IMO, I would just go either OE or OEM if you want better pricing. Brembo or Zimmerman are the OE manufacturers of BMW brakes. Check with ECS tuning on pricing.

On the M car, the difference in pricing for rotors and pads were minimum, but on other cars it could be significant as it was on my X5.

Brembo and Zimmerman also makes drilled versions too.

It's weird you CBS says it's still okay. Let me know what your measured thickness actually is. I dont' even know how it was possible bc the CBS estimate is based on the brake sensors. Sensors are usually replaced with every pad and rotor change. Maybe a faulty sensor? Is it an OE sensor?

[JNMiller]

It turns out that I was right. The rear pads wore abnormally. At least, I have not seen them wear like this in any other vehicle I have owned.

The inside pad had worn completely, only at the left rear. It was gone. Metal rubbing metal starting Friday night. The outside pad, where the sensor is, had not yet even worn down to the sensor, this no indication in the car that anything was wrong. Had I not heard and then looked, or were my girl using the car, for some extremely unlikely reason, it would have been driven like that for some time. Likely doing some damage.

I’d love to understand how one pad on the inside of the rotor wore so much faster than the one on the outside.

I’m going to order drilled and/or slotted rotors and more new pads nevertheless.

[arucano]

the asymmetrical wear of the pads are caused by the caliper not sliding freely on the pins. Check the condition of the pins and use a tiny bit of anti-seize to prevent maintain free lateral floating of the caliper.

[DerBosewicht]

Originally Posted by JNMiller

It turns out that I was right. The rear pads wore abnormally. At least, I have not seen them wear like this in any other vehicle I have owned.

The inside pad had worn completely, only at the left rear. It was gone. Metal rubbing metal starting Friday night. The outside pad, where the sensor is, had not yet even worn down to the sensor, this no indication in the car that anything was wrong. Had I not heard and then looked, or were my girl using the car, for some extremely unlikely reason, it would have been driven like that for some time. Likely doing some damage.

I’d love to understand how one pad on the inside of the rotor wore so much faster than the one on the outside.

I’m going to order drilled and/or slotted rotors and more new pads nevertheless.

Let me know if you find slotted rotors for a good price. While drilled and slotted looks amazing drilled Long letterman will have a shorter life than just doing the slotted or blanks... slotted is a happy medium for me.