AUDI A4 1999 B5 / 1.G Front Brake Service Workshop Manual

46-1


Front brakes, servicing Teves/Ate front brakes

WARNING!

Do not re-use fasteners that are worn or
deformed in normal use.
Some fasteners are designed to be used only
once, and are unreliable and may fail if used
a second time. This includes, but is not
limited to, nuts, bolts, washers, circlips and
cotter pins. Always follow recommendations
in this manual-replace these fasteners with
new parts where indicated, and any other
time it is deemed necessary by inspection.
To siphon brake fluid, always use a bleeder
bottle which is only used to siphon brake
fluid.
Brake fluid is poisonous and must NEVER be
removed by siphoning with your mouth.
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46-2


Note:
CAUTION!
Do not allow the caliper to hang by the brake
hose. The unsupported weight can stretch and
damage the hose.
Install complete repair kit.
After installing the brake pads, depress the
brake pedal firmly several times before moving
the vehicle to properly seat the brake pads in
their normal operating position.
The brakes can be tested on a commercial
brake dynamometer provided the speed of the
two dynamometer drive rollers is not more than
5.5 km/h (3.3 mph).
Tightening torque for the brake lines is 15 Nm
(11 ft lb)
1 -
Brake hose
Do not disconnect the brake hose from the
caliper when replacing brake pads.
2 -
Caps Remove for access to guide pin
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46-3


3 -
Guide pin
25 Nm (18 ft lb)
4 -
Brake line 15 Nm (11 ft lb)Install into caliper housingWhen tightening to brake hose, counter
hold on brake hose hex Make sure lugs are properly seated in
retainer grooves
5 -
Brake caliper housing Unbolt from brake carrier for replacing
brake pads Servicing brake caliper 47
-2
6 -
Ribbed bolt
125 Nm (92 ft lb)Clean ribbing if re-using
7 -
Brake carrier Bolt to wheel bearing housing
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46-4


CAUTION!
The inner brake pad (with expanding spring) is
marked with an arrow that must point in the
direction of rotor rotation when the vehicle is
moving forward. Incorrect installation can result
in excessive noise.
Note:
Before installing new brake pads, thoroughly clean
the brake calipers (free of grease). Pay particular
attention to removing any adhesive residue from
the outer brake pad contact surfaces. 8 -
Brake pads

Outer pads have an adhesive with a protective
sheet on the backing plate; remove this sheet
before installing
Different versions parts catalogue microfiche Always replace as a set on both wheels of an
axle
Removing and installing page 46
-7
Brake pad wear limit (friction material): 2 mm
(0.08 in.)
Brake pad wear limit (including backing plate): 7
mm (0.28 in.)
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46-5


CAUTION!
If the spring is not installed correctly, the outer
brake pad alignment mechanism will not be able
to compensate for wear, and increased pedal
travel will result. 9 -
Retaining spring
Insert into both holes in brake caliper
housing Once spring ends are seated in holes,
press retaining spring under brake carrier
10 -
Brake disc Always replace as a set on both wheels of
an axle To remove, first unbolt caliperResurface evenly on both sides starting
from thickness when new
Internally ventilated brake disc:Diameter: 288 mm (11.34 in.)Thickness: 25 mm (0.984 in.)Wear limit: 23 mm (0.906 in.)
Non-ventilated brake disc:Diameter: 288 mm (11.34 in.)
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Thickness: 15 mm (0.59 in.)Wear limit: 13 mm (0.51 in.)
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46-6


11 -
Bracket
Bolt to brake caliper housing
12 -
Hex bolt 10 Nm (7 ft lb)
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46-7

Teves/Ate brake pads, removing and
installing


Removing

Note:
If brake pads are to be re-used, mark their
installed positions when removing. Re-install in
the same positions, otherwise the car may pull to
one side!

- Raise vehicle.

- Remove wheels.

- Use screwdriver to pry brake pad retaining spring out of brake caliper
housing, and remove spring.

- Remove top and bottom caps (arrows).
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46-8


CAUTION!
Installing - Remove both guide pins from brake caliper.
- Remove brake caliper housing and secure to body.
Do not loosen brake hose or lines.Secure the brake caliper with a piece of wire in order to relieve the
stress on the brake hose. Do not allow the caliper to hang by the brake hose.
- Remove outer brake pad from brake carrier.
- Pull inner brake pad (with expanding spring) out of brake caliper piston.

WARNING!
Brake fluid is poisonous and must never be removed by siphoning
with your mouth. - Push piston back into brake caliper housing.
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46-9

CAUTION!

Extract part of the brake fluid from the brake
fluid reservoir before pushing back the
pistons.
If this is not done, particularly if the brake
fluid has been topped up in the meantime,
brake fluid may flow out and cause damage.
Use the bleeder bottle or a plastic bottle,
which is used only for brake fluid, for
extracting the fluid.
The inner brake pad (with expanding spring)
is marked with an arrow that must point in
the direction of rotor rotation when the
vehicle is moving forward. Incorrect
installation can result in excessive noise.

- Install inner brake pad (with expanding spring) in brake caliper piston
(left arrow). Arrow marked on pad must point in direction of rotor
rotation when vehicle is moving forward.
- Remove protective sheet from backing plate for outer brake pad.
- Install outer brake pad into brake carrier (right arrow).
- Bolt brake caliper housing to brake carrier using two guide pins.
Tightening torque: 25 Nm (18 ft lb)
- Install both caps.
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