| Tech Article Title |
Author
|
Date
|
|
Front Brake Pad Replacement (B6
S4/B7 All) |
AlanL
|
2004 |
Please note right up front - if you have never done brake work
before, STOP and go find a friend who has a clue to guide you through the
task. Brakes systems aren't terribly difficult to learn to work with, but
if you screw up the consequences can cause bodily harm to yourself and/or
others on the road.
The first task is to remove your wheel to
access the brakes.
The first task I did was to remove the
retaining spring that holds the caliper arm in position. To remove the
spring, use a screwdriver to get between the clip on the brake pad and the
bottom of the retaining spring. Push up on the screwdriver blade and then
pull towards you to get the locking tab of the spring to disengage from
the clip:
This will leave
the spring in place, but with the locking tab out of the slot in the
clip:
Use a
flat blade screwdriver to pry out the end of the spring arm. Use 2 hands
with one positioned to keep the spring from flying across the room once
it's released. I am using my other hand to take the picture in this
shot.
Next, spread
the calipers to get some play around the pads. Hint - open the cap on your
brake fluid master cylinder so the fluid can go back up the lines. If you
move the pads a lot, fluid can spill over the top of the master cylinder
reservoir.
Use 2 screwdrivers - one on each side of the caliper.
Kinda hard to show that and still shoot the picture.
The next
task is to remove the 2 bolts on the backside of the caliper that hold the
caliper in place so you can access the brakes inside. There are 2 plastic
dust caps the cover 7mm Allen bolts shown here with the red circles. If
your car is not on a lift, you can use a mirror to locate these
bolts:
Once you pull the
bolts out, you will find that you can lift the caliper off of the rotor
and you have full access to the pads for replacement. You may find it
helpful to have something like a paint can handy to hold up the caliper
while you change the pads as shown in this picture:
You will
probably need a brake caliper spreader to push the brake piston far enough
in allow the new pads to clear the rotor. This tool is readily available
at many auto parts stores.
The OEM pads in their
full glory of grime:
A good shot of the
pad wear sensor wires getting close to breaking the circuit and triggering
the dashboard warning lights:
The final task in
removing the old pads is to disconnect the wear sensor connector. First
remove the connector shell on the far side of the mounting bracket and
then use a small screwdriver to dislodge the short arm extending down on
the mounting bracket. Twist the pad connector and it will come out of the
mount bracket.
Once the
new pads are in, slide the caliper back over the rotor and replace the
bolts. slide one end of the retention spring under the arm of the caliper
and then position the tab of the retention spring behind the lip of the
brake pad clip.
Next, depress
the other spring arm and push it into place.
Finally, use
your thumb to push the retention spring tab back enough to engage the slot
of the clip:
Your
final view of the caliper should look like this:
That's it! Replace
the cap on the master cylinder and have someone pump the brake pedal until
it starts to get firm again (it will sink all the way to the floor for a
couple of strokes). Refill the master cylinder with enough fluid to reach
the fill line and replace the cap.
