There is a tutorial for replacing the front brake pads on this forum thanks to Mr5, and although changing the rears are very similar I thought I would document my change as a few people have been asking for the rears.

Please note: I am not a professional mechanic and have posted this information for the sake of information

Step 1: Jack your car up. If your car is lowered like mine you will have trouble getting the jack in the usual location, so I used the chassis where the rear wishbones connect. (I suspect they are not actually called rear wishbones so I'll let the pictures do the talking)


Step 2a: Remove the Brake Pad Sensor. It comes with a small clip that slides into the inn
er pad. The clip will probably not come out with the sensor and stay on the inner pad. Remember to remove it when you take off the pad.





Step 2b: Remove the front clip.


Step 3: Crack open the 2 bolts holding the calipers in place. I used a 5/8 socket.




PLEASE NOTE - The following pictures are now from the other side of the car (left side)


Step 4: With the 2 bolts removed, the caliper will slide out. It may be held in place from slight piston pressure. A bit of strength won't hurt here. Put a fuel can or a paint can under the hub so you can rest the caliper. DON'T LET IT HANG ON THE BRAKE LINE!!


Step 5: Remove the pads. They will slide out. The outside one isn't held by any clips.


The inside pad may resist as it has the clips inside the piston.




凌宝新能源Step 6: Pull the caliper bracket out, and clean. Ensure the sliders are clean of rust and fre
e to slide in an out. Some Water Displacement (WD40 or similar) spray works a treat.


.江铃4s店
.. and clean


钱江黄龙600图片Step 7: Push the piston back. Your new pads have double the meat as your old ones so you'll need space. I picked this Brake Caliper Tool from my local Auto Store (Repco or Supercheap Auto) for $13. You can also use a G-Clamp.
I used the old pad to spread the pressure over the piston.





超速50%Step 8: Insert new pads.
Ensure your new pads are the same as your old ones. ie. size and clips etc.
I put Anti-Squeal on my pads cause lets these mofo's squeal!!!

Do this - put paste on metal bits of back side of new pads. Also note the paste on the side where the metals will be touching.


DON'T DO THIS - the pads without the clips will be facing outwards and can be seen. Lu
ckily I had a high-pressure water cleaner and was able to clean off the anti-squeal paste.
The picture below shows the old pads on the left, and then new pads on the right.


豪沃
Inside Pad


Outer Pad


Step 9: Attach Caliper back onto hub. Just slide it on while ensuring your pads are put in straight, and there is enough clearance for the rotor. Once in place, put the bolts back on.

This picture also shows the front clip re-attached.


Step 10: CHANGE the brake pad sensor!!! See notes and photos below.


This photo demonstrates how the sensor sits on the inner brake pad. Put the clip on the sensor and slide it back into place.


On my car, the brake pad sensor was on the right hand side.


Don't forget to pump your brakes before using, and bed them in properly etc etc. You know the deal.

Good Luck




Go out and enjoy your Bimmer

edit: pictures below for changing rear brake pad sensor
you only need one sensor per axle

1. Remove wheel arch shrouding. Combination of 10mm plastic nuts and 8mm screws. You don't need to remove the whole thing, but I removed the whole thing for better viewing.






2. Locate Brake Pad Sensor - it's the white one. The picture below shows my holding up the new one next to it confirming size etc.



3. Replace old with new. I started from the connection, but you can start from the brake pad end. Un-clip the clips, replace old with new, and re-clip into position.



4. Image shows new sensor clipped into brake pad. It took a bit of fiddling to get it clipped in properly but easy enough.



5. Replace shrouding, wheels, bolts etc.

6. Reset Brake warning light in the dash. There are a few good threads about this already on the forum eg. www.e90post/ht=reset+brake. I haven't been able to get mine right despite trying everything under the sun, so I'm gonna make a trip to my indi BMW mechanic. FML
Brake pad sensor:
I replaced the rear pads per this DYI on my 2006 325xi. I tried to reset the onboard computer (OBC). I was able to reset the value from 3400 miles to minus 15,000 miles. Of course I got a red warning service indication and red "Brake" light. After some reading on the forum, I found that the sensor has a variable resistance and must be replaced if one wants the OBC to be reset to a positive number of miles.
I replaced the brake sensor (BMW #34356789445) and was able to reset the computer to
31,000 miles. All of the red warnings went away.
So, if you want the E90 onboard computer (OBC) to function correctly when brake pads are replaced, the sensor must be replaced!!! Or shortcutted!
I measured the DC resistance of the new sensor and old sensor.
New sensor = 0.5 ohms
Old sensor = 450 ohms
So, as the sensor wears down, the resistance goes up. This is in contrast to the E46 sensor that is an open(infinite ohms) or short(zero ohms) situation.
Slides: to remove plastic caps off of the back of the calipers and unscrew allen screws to take the calipers off. I'm wondering if those allen screws are actually for the bleeder valves?  These allen screws are actually the sliders so if you are going to change the sliders you will need to remove them.
明锐1.8tBleeding:
The two slider pins holding the pads that you remove are easy to find as they have rubber dust caps on them. Torque to 22lbs.
New brake sensors at the pad end are coated with plastic, if the pad has not worn down enough that it has started wearing off the plastic then you do not need to replace the cable or reset the service.
Before doing this go out and pick up some brake fluid, check the brake fluid cap, it will tell you what it needs, mine is p21s. Suction out the fluid reservoir before squeezing the pistons back in then suction it again after pushing the pistons in, fill the reservoir back up with fresh then bleed the brakes after you change the pads.