You didn't even post which BMW you are working on. It is hard to know your level of mechanical competence, but from the way you asked the question the best thing is to take the car to a mechanic and pay them to do it.
If you insist on doing it yourself, buy the correct Bentley manual for your BMW.
You can see the list of books here:
http://www.bentleypublishers.com/bmw
Buy it from Amazon or your local bookstore.
BMW brakes are much like the disc brakes on any modern car. The biggest difference is the parking brakes are inside the rear disks.
It is easy to replace the brakes if you know what you are doing. Even on cars like BMW's and Nissan's, the brakes are easily replaced.
Your brakes are getting low and you need to replace them.
Have to replace the brake sensors once you change the brakes and the computer will reset itself after a few minutes.
There is no need to spend the money if it doesn't need done. Typically your rotors last longer than your brakes do anyway, so you should be fine for a while.
You replace the brakes on an ABS S10 the same way you replace brakes on a non ABS S10.
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This will greatly depend on what kind of brakes you have and which parts you are trying to replace. Do you have disc or drum brakes? If you have disc brakes, do you want to replace the calipers, pads, or rotors? If you have drum brakes, do you want to replace the drum, or the shoes?
just replace the rear brakes
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