Originally Posted by Efthreeoh
Well, no it is always active and is designed to compensate for the avaialble traction at each wheel during braking. The front brakes on all cars are larger than rear brakes because they are designed to take the majority of the braking load to stop a car. EBFD allows for the system to effectively use the rear brakes more as they can be controlled through the ABS hardware not to lock but give maximum braking force during braking. Being there is a size difference between the front and rear brakes, in most situations with BMWs, which have near perfect weight distribution, the front and rear brakes tend to wear at the same rate. As evidence, I've gone through two sets of brakes and all four wore out within 2,000 miles of each other - this happened twice, once at 75K and again at 193K.
You are partially correct. Yes it is always active, but on standby. For normal braking conditions, the difference from front to rear is designed into the master cylinder and is called brake bias. EBFD controls the brake bias in heavy braking along with DSC activation. Normal driving is purely mechanical on all BMW cars. If your brakes last that long you either drive mostly highway or drive like grandma. My X5 goes through front pads and roters every 19k miles and rears every 35k miles. My 335 goes through rear pads first. My rears are good for an average 16k miles and fronts 30k+ if were to leave them on. If you "DRIVE" a BMW, you do not get even pad life. You get your brake life based on you driving style not the vehical.