Originally Posted by Tate325xi
I don't have access to a lift, do you think it can be done with a breaker bar on jackstands? And what size of breaker bar do I need?
no pun intended... I am a 63 years old Asian man, weighing 135Lbs and I did not have any difficulties taking apart all four floating calipers with standard 1/2 inch drive torque and socket wrenches. First, I doused all the parts to be taken apart with brake cleaner spray, then I sprayed with liquid wrench (wd40 will do too). You are gonna to have ground clearance problems if you do not use lifts. Using wheel jacks, make sure you have a second stationary stand too. Can you rent either an air impact wrench? or may be an electrical one? Impact wrenches are like magic; any hard bolts will be loosened effortless.
BTW, you do not have to remove the caliper units, you just loosen the aluminum shear pins that hold the floating calipers, unsnap the anti-rattling springs, compress the pads, and your floating calipers will come out very nicely. You need to loosen the high torque bolts to remove the caliper unit if you intend to replace the rotors. I have seen e46 fanatics doing this in the field before the start of a "track" event.
Theoretically if the tips of the sensors are not worn, you can re-use them; but in real life most likely you will break the metal clips when you yank them out, and once its flimsy metal clips are bent it is almost impossible to snap back in place again. I just replace them with new ones, one for the front driver side and one for rear passenger side. Use a strong flashlight and a thin flat head screw driver to guide the metal clips so it will snap in place.
Since the the sensors are snapped unto the indentation of the pads, beware that some aftermarket brands are not truly made for BMW, so the sensors will not snap back firmly. I had very bad experience with EBC and Centric. Akebono on the other hand, was like a custom made to fit the oem ATE calipers, from its nicely machined back, riveted anti squeal shim and a very deep and nicely shaped pocket for the sensors to be snapped in.