How do you know when you need new rotors?

[Steve1155]

My car is almost out of maintenance warranty and I'm hoping to get the rotors replaced before its too late. If the rotors are still good then obviously BMW will not replace them. So how to tell if they need replacing?

[pixelblue]

if the thickness has gone below a certain point you need to change them. the dealer can measure the thickness

[BMWbab1]

More than likely you will get a wiggle in your steering (due to uneven wear) well before you ever need a new set of rotors due to thickness.

[AW128i]

When the BC indicated that the front brakes were due last year, the dealer replaced the pads and rotors. When the BC said the rear brakes needed replacement (also last year), the dealer replaced the pads and rotors. So, I'm thinking that BMW replaces them together??

I'm actually curious about this. According to the BC, my front brakes are due in about 6,000 miles. I want to take the opportunity to switch to aftermarket pads and I'm unsure if I should replace the rotors as well. Anyone know the minimum thickness?

[chachacha28]

the dealer will almost always do pads and rotors together. i think i heard somewhere that oem bmw rotor life is 1.5x the pad life. so if your pads need to be replaced today, the rotors will need to be replaced before your replacement pads run out. hopefully that makes sense.

[BFD99]

Mine did pads only, said the rotors were .01 or .02 from being out of spec though, this was in january, my car goes in friday, hoping they get changed this time around as my maintence plan almost runs out!