1994 BMW M3 brake pads

340-
4
BRAKES

Fig
.
2
.



Front
brake
caliper
assembly
.

Bleeder
valve
and
dust
cap

Mounting
bolt

Brake
pad
wearsensor
(left
wheel
only)

-
Brake
pad
.
carrier
Anti-rattle
^_
spring-

0012154

Fig
.
3
.



Brake
caliper
guide
bolts
(arrows)
.

5
.
Pull
caliper
straight
off
rotor
.

CAUTION-

Do
not
let
the
brake
cafiper
hang
from
the
brake
hose
.
Suspend
ft
from
the
chassis
using
stiff
wire
.

BRAKE
PADS,
CALIPERS,
AND
ROTORS

0012155

Fig
.
4
.



Removing
anti-rattle
clip
by
unhooking
at
top
and
bottom
.
Use
screwdriver
asan
aid
(arrow)
.

NOTE-

If
there
is
a
ridge
on
the
rotor
edge,
the
cafiper
pfston
will
have
to
be
pushed
back
finto
the
cafiper
before
the
cafiper
can
be
removed
.

6
.
Remove
brake
pads
from
caliper
.
Where
applicable,
carefully
pry
pad
wear
sensor
from
pad
.
See
Fig
.
5
.

Fig
.
5
.



Removing
brake
pad
wear
sensor
.

7
.
Inspect
brake
caliper
for
signs
of
leakage
.
Check
that
the
caliper
piston
slides
smoothly
into
caliper
.
Replace
caliper
if
any
faults
are
found
.

CAUTION-

With
the
pads
removed,
residual
hydreulic
pres-
sure
may
cause
the
caliper
piston
to
slide
out
.
Use
a
wooden
block
to
hold
the
piston
in
place
.

8
.
fnsert
brake
pad
wear
sensor
into
cutout
in
new
pad

where
applicable
.

14
.
Place
inner
brake
pad
(with
locating
spring)
ontobrake
NOTE-



caliper
piston
.
Route
pad
wear
sensor
wiring
through
lf
the
brake
lining
indicator
light
illuminated
prior
to



caliper
opening
and
bleeder
dust
cap
.
brake
pad
replacement,
the
wear
sensor
should
be
re-
placed
.



15
.
The
remainder
of
installation
is
reverse
of
removal
.

"
Do
not
lubricate
guide
boits
.
9
.
Slowly
press
piston
back
into
caliper
.
Use
cace
not
to



"
Once
brake
assembly
is
installed
depress
brakepedal
damage
piston
dust
sea¡
.
See
Fig
.
6
.



severa¡
times
before
driving
vehicle
.

NOTE-

"
Open
caliper
bleeder
screw
when
pressing
piston



Tightening
Torques

back
into
caliper
.
Catch
expelled
fluidin
appropriate



"
Brake
caliper
to
brake
pad

container
.
This
procedure
is
highly
recommended
in



carrier
(guide
bolt)
..........
...
.
.
30
Nm
(22
ft-Ib)

the
case
of
cars
with
ABS
.



"
Road
wheel
to
hub



.....
.
..
100±10
Nm
(74±7
ft-Ib)

"
Open
the
bleeder
screw
only
when
applying
force
to
the
piston
.
Do
not
allow
airto
be
drawn
in
through
the
bleeder
screw
.

"
Pressing
the
caliper
piston
in
may
cause
the
brake
flu-
id
reservoir
to
overflow
.
To
prevent
this,
use
a
clean
syringe
to
first
remove
some
fluid
from
the
reservoir
.

BRAKES
340-
5

0012157
Fig
.
6
.



Brake
caliper
piston
being
pressed
into
caliper
to
make
room
for
new
pads
.
Usea
rag
toprotect
caliper
piston
and
seals
.

10
.
Thoroughly
clean
inner
and
outer
surfaces
of
brake
ro-
tor
.
Inspect
rotor
for
cracks,
signs
of
overheating
and
0012156
scoring
.

11
.
Measure
thickness
of
rotor
.
See
Table
b
.
If
rotor
does
not
pass
minimum
thickness
requirements,
or
is
dam-

aged,
replace
as
described
later
.

12
.
Thoroughly
clean
all
contact
points
on
caliper
and
brake
pad
carrier
.
Clean
guide
bolts
and
make
surethey
slide
freely

13
.
Lightly
coat
pad
contact
points
with
brake
anti-squeal
paste
.
Place
outer
brake
pad
onto
caliper
.
Applya
small
amount
of
grease
to
thetop
and
bottom
contact
points
where
the
caliper
contacts
the
pad
carrier
.

BRAKE
PADS,CALIPERS,
ANDROTORS

340-
6BRAKES

bolt~



Guide
bolt

caps
covers
Brake
caliper
Shoe
retaining
píns

Parking
brake
cable

Fig
.
7
.



Rear
brake
caliper
assembly
.

Caliper
guide



Brake



ad
bolts
,



Bleeder
valve



i
_
~wear
sénsor
®



and
dust
cap



(right
wheel
V
.
.,,,

Brake
caliper,
removing
and
installing

1
.
Raise
car
and
remove
wheel
.

WARNING
-

Make
sure
the
car
is
firmly
supported
on
jack
standsdesigned
for
the
purpose
.

2
.
Loosen
brake
hose
fitting
at
caliper
.
Do
not
remove
.

3
.
Remove
caliper
mounting
bolts
from
steering
arm
(Font

caliper)or
from
trailing
arm
(rear
caliper)
.
See
Fig
.
8
.

4
.
Press
piston
back
into
caliper
and
slide
caliper
off
brake

rotor
.
Spin
caliper
off
brake
hose
.

5
.
Inspect
brake
caliper
for
signs
of
leakage
.
Check
that
caliper
piston
slides
smoothly
into
caliper
.
Replace
cal-

iper
if
any
faults
are
found
.

6
.
Installation
is
reverse
of
removal
.
Bleed
entire
brake

system
before
driving
car
.
See
Bleeding
Brakes
.

Tightening
Torques

"
Front
brake
caliper
to
steering
arm
..
110
Nm
(81
ft-Ib)

"
Rear
brake
caliper
to
trailing
arm
....
67
Nm
(50
ft-Ib)

"
Brake
fluid
hose
to
caliper
....
17-19
Nm
(13-14
ft-Ib)

"
Road
wheel
to
hub



........
100±10
Nm
(74±7
ft-Ib)

BRAKE
PADS,CALIPERS,
ANDROTÓRS

Cover

Caliper



!



Brake
pad
Oringiston



carne
-
p

Circli

©
ot~
AV
~:
Z



1vo~
Spring
and
spring
retainer



uust
seas



~~



Aniráttle

j),
Brake



spring
Shoe
pads
_
_

adjuster



per
return

nf

MIL

Rotor
with
integrated
parking
brake
drum
6573

0011256

Fig
.
8
.



Front
brake
pad
carrier
mounting
bolts
(arrows)
.
Rear
caliper
mounting
bolts
are
similar
.

Brake
rotor,
removing
and
installing

Brake
rotors
shouldalways
be
replaced
in
pairs
.

Fig
.
9
.



Brake
rotor
mounting
screw
(arrow)
.

3
.
Inspect
rotor
for
excessive
grooving,
cracks,
and
warp-

ing
.
Check
rotor
thickness
.
See
Table
b
.

4
.
Installation
is
reverse
of
removal
.

"
Clean
rotor
with
brakecleaner
before
installing
.

"
If
brake
fluid
hose
veas
removed
or
loosened,
brake

systemmustbe
bled
as
described
aboveunder

Bleeding
Brakes
.

BRAKES
340-
7

5
.
Once
brake
assembly
is
instalind,
depress
brakepedal

several
times
to
adjust
caliper
and
pads
.

"
Pedal
should
feel
firm
and
be
at
proper
height
.

"
Check
fluid
leve¡
.
Top
up
if
necessary
.

NOTE-

M3
models
use
directional
brake
rotors
and
mustbe
in-



NOTE-

stalled
on
the
proper
side
.
Part
numbes
are
cast
finto



When
installing
new
rear
brake
rotors,
the
parking

therotors
.
A
part
that
ends
in
an
odd
number
is
a
left



brakeshouldbe
adjusted
.
See
Parking
Brake
.

rotor
.
One
that
ends
in
an
even
number
is
a
right
rotor
.

1.
Remove
caliper
as
described-above
and
hang
from



Tightening
Torques
chassis
using
stiff
wire
.



"
Brake
rotor
to
wheel
hub
..........
16
Nm
(12
ft-Ib)

"
Front
brake
caliper
to
steering
arm
...
110
Nm
(81
ft-Ib)

NOTE-



"
Rear
brake
caliper
to
traíling
arm
....
67
Nm
(50
ft-Ib)

Do
notloosen
caliper
brake
hose
.



"
Road
wheel
to
hub



...
..
.
100
±
10
Nm
(74
t
7
ft-Ib)

2
.
Remove
mountingscrew
holding
rotor
to
wheel
hub
.



,

See
Fig
.
9
.



Table
b
.
Brake
Rotor
Reconditioning
Specificati*M`

Front
Rear

Vented
rotor
wear
limit
(min
.
thickness)



20
.4
mm
(0
.803
in.)

Solid
rotor
wear
limit
(min
.
thickness)



8
.4
mm
(0.331
in
.)

M3
models
wear
limit
(min
.
thickness)



26
.4mm
(0
.977
in
.)



18
.4
mm
(0
.723
in
.)

Axial
runout
(max
.)
rotor
removed



0
.05
mm
(0
.002
in
.)



0
.05
mm
(0
.002
in
.)
rotor
installed



0
.20
mm
(0
.008
in
.)



0
.20
mm
(0
.008
in
.)

CAUTION-

M3
brake
rotors
must
not
be
machined
.

MASTER
CYLINDER

The
brake
master
cylinder
is
mounted
to
the
front
of
the
vac-

uum
booster
on
the
driver
side
bulkhead
.

Master
cylinder,
removing
and
installing

1
.
Using
a
clean
syringe,
empty
brake
fluid
reservoir
.

WARNING
-

Brake
fluid
is
highly
corrosive
and
dangerous
to
the

environment
.
Dispose
of
it
properly
.

NOTE-

On
original
equipment
rotors,
the
mínimum
allowable



2
.
Disconnect
brake
fluid
leve¡
sender
connector
from
fluid

thickness
is
stamped
on
the
rotor
hub
.
Measure
the
rotor



reservoi
r
cap
.

brakingsurface
with
a
micrometer
at
eight
to
ten
different

points
and
use
the
smallest
measurement
recorded
.



3
.
Disconnect
brake
fluid
lines
frommaster
cylinder
.
See

Fig
.
10
.
Disconnect
hydraulic
clutch
system
supply
line
.

4
.
Unscrew
mounting
nuts
and
remove
master
cylinder

from
brake
booster
.

5
.
Make
sure
all
nuts,
fluid
couplings,
thread
bores,
and

mating
surfaces
are
clean
.

MASTER
CYLINDER

7
.
Turn
on
ignition
.
Check
that
light
comes
on
as
soonas



4
.
Remove
parkíng
brake
shoes
as
described
above
.

lever
is
pulled
up
.
5
.
Disconnect
cable
from
parking
brake
actuator
and
then

8
.
Install
parking
brake
lever
boot
.
Install
road
wheel
lug



remove
parking
brakecable
from
cable
holder
on
trail-

bolts
.



ing
arm
.
See
Fig
.
17
.

Tightening
Torque

"
Road
wheel
to
hub
.
..
......
100±10
Nm
(74±7
ft-Ib)

Parking
brake
shoes,

removing
and
installing

1.
Raise
rear
of
car
andremove
road
wheels
.

WARNING
-

Make
sure
the
car
is
firmly
supportedon
jack
stands

designed
for
the
purpose
.
Place
the
jack
stands
be-

neath
a
structural
chassis
point
.
Do
not
place
jack

stands
undersuspension
parts
.

2
.
Without
disconnecting
brake
fluid
hose,
remove
rear

brake
calipers
from
trailing
arms
.
Remove
rear
brake

rotors
.
See
Brake
Pads,
Calipers
and
Rotors
.

CA
UTION-

Do
not
let
the
brake
caliper
assembly
hang
from

the
brake
hose
.
Support
caliper
from
chassis
with
strong
wire
.

3
.
Unhook
upper
return
spring
from
brake
shoes
.
Remove

shoe
retainers
bypushing
them
in
and
rotating
1
/4turn
.

BMW
special
tool
no
.
344
000
can
beused
to
remove

retainers,
if
needed
.

4
.
Spread
shoes
apart
and
lift
them
out
.



7
.
Installation
is
reverse
of
removal
.
Adjust
parking
brake

as
described
earlier
.

NOTE-

When
removing
the
brake
shoes
the
shoe
expander
pivot
pin
in
the
brake
actuator
may
fall
out
.

Two
versions
of
the
Antilock
Brake
System
(ABS)
are
in-

5
.
Inspect
shoe
expander
to
make
sure
it
functions
prop-



stalled
onthe
cars
coveredby
this
manual
.
Early
cars
use
the

erly
.
Apply
a
thin
coat
of
grease
tosliding
parts
and



Teves
Mark
IV
G
ABS
.
Later
cars
use
the
Teves
Mark
20-I

pins
.



ABS
.
The
main
difference
between
the
two
systems
is
that
the

Mark
20-I
system
integrates
the
ABS
control
module
into
the

6
.
Installation
is
reverse
of
removal
.
Be
sure
to
adjust



hydraulic
unit
as
a
single
component
.

parking
brake
cables
as
described
earlier
.

ABS
is
designed
to
be
maintenance
free
.
There
are
noad
Parking
brake
cable,
replacing



justments
that
canbe
made
to
the
system
.
Repair
and
trouble-

shooting
of
the
major
ABS
components
requires
special
test

1
.
Raise
rear
of
car
and
remove
road
wheels
.



equipment
and
knowiedge
and
should
be
done
by
an
autho-

rized
BMW
dealer
.

2
.
Remove
rear
brake
caliper
and
rotor
.
See
Brake
Pads,

Calipers
and
Rotors
.

3
.
Working
inside
car,
lift
parking
brake
lever
boot
out
of

console
.
Remove
cable
adjusting
nut
.
Refer
to
Fig
.
15
.

Fig
.
17
.
Parking
brake
cable
insertion
point
in
rear
trailing
arm
(arrow)
.

6
.
Slide
cable
out
of
housing
.

NOTE
-

BRAKES
340-
1
1

On
some
models
it
may
be
necessary
to
remove
rear

muffler
to
access
the
brake
cabes)
.

ANTILOCK
BRAKE
SYSTEM
(ABS)

0013209

ANTILOCK
BRAKE
SYSTEM
(ABS)

WARNING

Your
common
sense,
good
judge-

ment,
and
general
alertness
are
cru-

cial
to
safe
and
successful
service

work
.
Before
attempting
any
work
on

your
BMW,
read
the
warnings
and

cautions
on
page
vi¡
and
the
copyright
page
at
the
front
of
the
manual
.
Review
these
warnings
and
cautions
each
time
youprepare
to
work
on
your
BMW
.
Please
also
read
any
warnings
and
cautions
that
accom-

pany
the
procedures
in
the
manual
.

A

ABS
(anti-lock
brakes)

See
Brakes
Accelerator
and
throttle
linkage
See
Maintenance
program
Air
conditioning
general
information
640-1
air
distribution
motor,
replacing
(rotary

knob)
640-10
air
distribution
motors
640-9

blower
motor,
removing/installing

640-1blower
motor
resistor
pack,
replacing
640-3
compressor,
replacing
640-12
compressor
clutch
640-13
condenser,
replacing
640-14
control
head
640-7
removing/installing
(digital
-display)

640-8
removing/installing
(rotary
knob)

640-7
control
module
removing/installing
(digital-display)
640-8
removing/installing
(rotary
knob)
640-8
evaporator,
removinglinstalling

640-17
evaporator
temperature
sensor,

replacing
640-17

expansion
valve,
removing/installing

640-16
microfilter,
replacing
640-18
receiverldrier,
replacing
640-15
sensor
fan
forinterior
temperature,

replacing
640-9
warnings
and
cautions
640-11

Air
distribution
(flap)
motor

See
Air
conditioning
See
also
Heating
Air
filter
See
Maintenanceprogram

Airbag
system
(SRS)
general
information
721-1

contact
ring,
replacing
721-3

driver
side
airbag,removing/installing

721-5
front
crash
sensor,
replacing
721-4

front
side-impact
airbag,
removing/
installing
721-7

front
side-impact
airbag
crash
sensor,

removing/installing
721-5

passenger
side
airbag,
removing/

installing
721-6
sensors
and
electronics
721-1

SRS
warning
light
and
fault
display

721-2
systems
721-1
ZAE
control
module,
replacing
721-5

Alarm
system
See
Central
locking
and
anti-theft

Alternator
See
Battery,
starter,
alternator

Anti-freeze
(Engine
coolant)

See
Maintenance
program

Anti-theft
See
Central
lockíng
and
anti-theft

AST
(Al¡
season
traction)
300-4

ATF
(Automatic
transmission
fluid)

See
Automatic
transmission

Automatic
transmission

See
alsoTransmission-general
general
information
240-1

ATF,draining
and
filling
240-2

ATF
leve¡,
checking
240-1
transmission
removaland
ínstallation

240-4
transmission,
removinglinstalling
240-4
transmission
service
240-1

Auxiliary
fan
See
Cooling
system
Axle
joint
See
Maintenance
program

B

Back-up
light
switch
See
Manual
transmission
Balljoint
See
Front
suspension
Battery
See
Battery,
starter,
alternator

Battery,
starter,
alternator
See
also
Maintenance
program
general
information
121-1

alternator,
removing/installing
(4-
cylinder
engine)
121-5
alternator,
removinglinstalling
(6-
cylinder
engine)
121-6
alternator
brushes,
inspecting/
replacing
121-7
alternator
service
121-4
batterycharging
121-4
battery
load
voltage
test
121-4

batteryopen-circuit
voltage
test
121-4

battery
service
121-3

INDEX
1

Battery,
starter,
alternator
(cont
.)
battery
testing
121-3
charging
system
quick
check121-2
charging
system
troubleshooting
121-
2
hydrometer
testing
121-3
solenoid
switch,
removinglinstalling
121-10
starter
service
121-7
starter
troubleshooting
121-7
starter,
removing/installing(4-cylinder
engine)
121-8
starter,
removing/installing(6-cylinder

engine
with
automatic
transmission)

121-9
starter,
removing/installing
(6-cylinder
engine
with
manual
transmission)
121-8
static
current
draw,
checking
121-2
voltage
regulator,
removing/installing
121-6
Bearing,
wheel
See
Front
suspension
or
Rear

suspension
Blowermotor
See
Air
conditioning
See
also
Heatíng
BMW
emblem
See
Exterior
trim,
bumpers
Body-general
general
information
400-1

body
assembly
400-1
central
body
electronics
400-4
convertible
models
400-2
coupe
models
400-2
electronic
immobilizatíon
system
400-
4
exterior
and
aerodynamics
400-2

heating
afhdair
conditioning
400-5

instruments
and
controls
400-4
interior
equipment
400-3
seats
and
seatbelts
400-3
Body
side
molding
See
Exterior
trim,
bumpers

Brake
fluid
See
Maintenance
program

Brakes
general
information
340-1
antilock
brake
system
(ABS)
340-11
inspection
340-12
wheelspeed
sensors,
replacing

340-12
bleeding
brakes
340-3
brake
booster,
removinglinstalling
340-8
brake
caliper,
removing/installing

340-6
brake
pads,
calipers,
and
rotors
340-3

brake
pads,
replacing
340-4
brake
rotor,
removing/installing
340-7
master
cylinder,
removing/installing

340-7
parking
brake
340-10
adjusting
340-10
.
cable,
replacing
340-11
shoes,
removinglinstalling
340-11