Tire BMW 328i 1997 E36 Owner's Manual

300-2



SUSPENSION,
STEERING
AND
BRAKES-GENERAL

Steering

INTEGRATED
SYSTEMS

The
steering
linkage
connects
the
rack-and-pinion
unit
through
tie
rodsto
the
steering
arms
.
The
tie
rod
ends
allow
the
wheels
to
pivot
and
react
to
suspension
travel
.

Rear
Suspension

The
rear
axle
carrier
is
the
main
mounting
point
for
the
final

drive
housing
and
the
rear
suspension
components
.

Trailing
arms
locatethe
rear
wheels
and
anchorthe
springs,

shocks
and
stabilizer
bar
.
Driveaxies
with
constant-velocity

(CV)
joints
at
both
ends
transfer
power
from
the
differential
to

the
road
wheels
.
The
differential
is
mounted
to
the
rearaxle

carrier
through
rubber
mountsand
bushings
to
hele
isolate

drivetrain
noise
and
vibration
.

Brakes

E36
cars
areequipped
with
power
disc
brakes
with
an
inte-
gral
antilock
brakes
(ABS)
.
The
parking
brake
is
a
dual-drum

system
integrated
with
the
rear
brake
rotors
.
See
Fig
.
3
.

Power
assist
is
provided
by
a
vacuum
booster
when
the
en-

gine
is
running
.
The
brakepedal
pushrod
is
connected
directly

to
the
master
cylinder,
so
failure
of
the
vacuum
booster
does

not
normally
result
in
total
brake
failure
.

0012124



Each
disc
brakeuses
a
caliper
with
a
single
hydraulic
cylin-
Fig
.
2
.



Front
suspension
control
arm
(arrow)
.



der
.
Brake
pads
in
the
left
front
and
right
rear
contain
wear

sensors
.
When
the
padsneed
replacement,the
sensors
illu-
The
front
suspension
is
designed
with
minimum
positive



minate
a
light
on
the
dashboard
.
steering
offset
.
This
geometry
contributes
to
stability
when

traction
is
unequalfrom
side
to
side
.
Suspension
travel
is
lim-



Tires
and
Wheels
ited
by
rubber
bump
stops
.

The
three
point
mounting
of
each
L-shaped
control
arm
ere-



Tiresize
is
critica¡
to
the
proper
operatíon
of
the
E36
ABS
or

cisely
controls
the
front-to-rear
and
side-to-side
position
of
the



ABS/AST
system
.
Severa¡
different
styles
of
wheels,
in
15,16

strut,
while
the
flexibility
of
the
joints
and
mounts
alsoallows



and
17
inch
diameters,
are
available
from
an
authorized
BMW

the
movement
necessary
for
suspension
travel
.
The
control



dealer
.

arm
mounting
points
are
designed
with
anti-dive
geometry
.

The
suspension
reduces
the
normaltendency
for
the
front
of



NOTE-
the
vehicle
to
dive
under
hard
braking
.



Aftermarket
wheelsshould
be
selected
wlth
care
.
Im-
properly
fitted
wheels
can
contact
anddamage
sus

Control
arm
position
is
fixed,
with
no
adjustment
provisions



pension,
brakeorbodycomponentsandmayadversely

on
the
control
arms
for
alter¡ng
front
wheel
al
ignment
.
A
stabi-



affect
vehicle
stability
.

lizer
bar
mounted
to
both
control
arms
heles
to
reduce
body
rol¡
whencomering
.



INTEGRATED
SYSTEMS

Antilock
Brake
System
(ABS)
is
standard
on
all
E36
cars
.

The
variable-assist
power
steering
system
consists
of
an



Standard
on
some
models
and
installed
as
optional
equipment
on

engine-driven
hydraulic
pump,
a
rack-and-pinion
type
steer-



others,
is
All
Season
Traction
(AST)
.

ing
gear,
and
connecting
linkage
to
the
road
wheels
.
TheE36
utilizes
an
engine-speed
dependent
variable
effort
steering



Antilock
Brake
System
(ABS)

system
.
At
low
speeds,
maximum
power
assist
is
provided
to
ease
parking
and
city
driving
.
Athigh
speeds,
assist
is
re-



The
electronically-controlled
ABS
maintains
vehícle
stabili
duced
to
ensure
stability
.



ty
and
control
during
emergency
braking
by
preventing
wheel
lock-up
.
ABS
provides
optimum
deceleration
and
stability
dur-

300-4



SUSPENSION,
STEERING
AND
BRAKES-GENERAL

Three-channel
ABS
ís
used
on
al[
E36
cars
equipped
with



Al¡
Season
Traction
(AST)
standard
ABS
.
Each
front
wheelhas
a
separate
solenoid

valve
to
modulate
hydraulic
pressure
to
that
brake
caliper
.



The
traction
control
system
works
in
conjunction
with
ABS
The
rear
wheels
are
modulated
asa
pair,
controlled
by
a
sin-



and
the
engine
management
system
to
enhance
vehicle
con
gle
solenoid
valve
.



trol
.
The
main
function
of
the
AST
system
is
to
maintain
the
rolling

contact
between
the
tires
and
the
road
surface
under
al¡
driving
E36
cars
equipped
with
ABS/AST
utilize
a
four
channel
sys-



conditions
.
This
is
achieved
through
exact
application
and
tem,
which
functionsexactly
as
the
three
channelsystem



management
of
braking
and
drivetrain
forces
.
above,except
that
the
rear
wheels
are
modulated
individually
.

IDLE
SPEED
CONTROL
VALVE

HROTTLE
PLATE

6
.

Í
III

i



ADS
ACTU
AT
OR

THROTTLE
PLATE
POSITION
SENSOR

DME

Fig
.
6
.
All
Season
Traction
(AS)
works
withother
drivetrain
systems
to
enhance
vehicle
control
.

INTEGRATED
SYSTEMS

The
throttle
control
system
used
in
AST
is
illustrated
in
Fig
.

MASS
AIR
FLOW
SENSOR

JADS
THROTTLE
PLATE
POSITION
SENSOR

0013006

NOTE-

The
traction
control
system
referred
to
as
AST
(all
sea-
son
traction)
may
also
be
referred
to
as
ASC
(Automat-
ic
Stability
Control)
and
ASC+T
(Automatic
Stability
Control+Traction)
.

The
AST
system
improves
traction
by
electronically
apply-

ing
the
rear
brakes
when
therear
drive
wheels
are
spinning
at

a
faster
rate
than
the
front
wheels
.
The
combined
ABS/AST

control
module,
operating
through
the
ABS
hydraulic
control

unit,
modulates
braking
force
at
therear
wheels
.

In
addition,
AST
uses
retarded
ignition
timing
and
an
auxil-iary
engine
throttle
plate
to
reduceengine
torque
and
maintain

vehicle
stability
.

The
auxiliary
throttle
plate
is
held
open
by
spring
pressure
.

The
AST
system
actívates
the
auxiliary
throttie
position
motor

(ADS)
to
cose
the
AST
throttle
as
needed
.
This
reduces
the

volume
of
engine
intake
air
.
Due
to
the
throttle
closing
very
rapidly
during
AST
operationthe
driver
cannot
increase
theengine
power
output
regardless
of
how
far
theaccelerator
pedal
is
pushed
to
the
floor
.

The
auxiliary
throttle
plate
is
placed
ahead
of
the
conven-

tional
throttle
plate
in
the
throttle
body
.

Traction
control
also
comes
into
operationduringdecelera-
tion
.
Decelerating
on
snowy
or
icy
road
surfaces
can
lead
to
rear
wheel
slip
.
If
a
rear
wheel
startsto
drag
or
lock
up
when

the
throttle
is
closed
rapidly
orduringdownshifting,the
AST
system
can
limit
the
problem
by
advancing
the
ignition
timing
.

A
switch
on
the
center
console
is
used
to
togglethe
AST
on

or
off
.

The
AST
system
is
designed
to
be
maintenance
free
.
There

are
no
adjustments
that
can
be
made
.
Repair
and
trouble-
shooting
of
the
AST
system
requires
special
test
equipment

andknowledgeand
should
be
performed
only
by
an
autho-

rized
BMW
dealer
.
Table
a
lists
theconditions
indicated
by

the
AST
indicator
light
in
the
instrument
cluster

SUSPENSION,
STEERING
AND
BRAKES-GENERAL



300-5

Tablea
.
AST
Indicator
Lamp
Function

Indicator
lamp



1
Condition



1
Comment

Light
on



Normal
AST
start-



Automatic
AST
up



self-test

Light
off



AST
monitoring



Automatic
AST
op-
mode



eration

Press
AST
button,



AST
off
(disabled)



Rocking
the
car
tolight
comes
on



getout
of
snow
or
other
loose
surface
Driving
with
snow
chains

Press
AST
button
:



AST
monitoring



Automatic
AST
op-
light
goes
out



I
mode



eration

Light
flashes



AST
active
mode



I
Normal
AST
oper-
ation
as
it
controls
wheel
speed

Light
stays
on
af-



Defect
in
AST



Consult
BMW
ter
start
up
or



dealer
for
diagno-
comes
on
while



sis/repair
driving



(Vehicle
operation
remains
normal)

WARNING
-

Even
a
car
with
AST
is
subject
to
the
normal
physi-
cal
laws
.
Avoid
excessive
speeds
for
the
road
con-
ditions
encountered
.

CAUTION-
"
If
the
tires
on
the
carare
of
different
makes,
the
AST
system
may
over-react
.
Only
fit
tires
of
the
same
make
and
tread
pattem,

"In
adverse
conditions,
such
as
trying
to
rock
the
car
outof
deep
snow
or
another
soft
surface,
or
when
snow
chainsare
fitted,
it
is
advisable
to
switch
off
AST
and
allow
the
cars
driveline
to
op-
erate
conventionally
.

INTEGRATED
SYSTEMS

increased
power
output
and
road-handling
demands
.

The
steering
geometry
is
modified
by
changing
the
cast-

er/camber
angles
slightly
.
This
is
accomplishedby
reposition-

ing
the
upper
strut
mounting
holes
in
the
frontstrut
towers
and

through
different
front
and
rear
control
arms
.

M3
Brake
System
Improvements

"
Vented
directionalfront
rotors
:
315
mm
dia
.
x
28
mm
thick
.

"
Vented
directional
rear

rotors
:
312
mm
dia
.
x20
mm
thick
.

"
Larger
brake
pads
and
calipers
.

"
Modified
Teves
ABS
system
.

SUSPENSION,
STEERING
AND
BRAKES-GENERAL



300-
7

M3
SUSPENSION
AND
BRAKES



NOTE-

M3
brake
rotors
are
directional,
having
a
different
part

TheE36
M3
was
introduced
in
late
1994
as
a
1995
model
.



number
for
each
side
.
Rotors
with
an
odd
part
number

The
design
of
the
M3
suspension,
steering
and
brakes
is
a



go
on
the
left
while
rotors
with
en
even
part
numbergo

modification
of
existing
E36
systems
which
accommodates



on
the
right
.

M3
Front
SuspensionImprovements

"
Reinforced
spring
plates,control
arms,
control
arm
bush-

ings,
steering
arms
.

"
Recalibrated
struts,
firmer
springs
.

"
Stiffer
stabilizerbar,
larger
stabilizer
bar
bushings
.

"
Front
stabilizer
linked
to
struts
.

M3
Wheels/Tires

"
Front
wheels
1992-1998
:.....
7
.5J
x
17
in
.
light
alloy

"
Rear
wheel
1992-1997
.......
7
.5J
x17
in
.
light
alloy

"
Rear
wheel
(option)
........
.8
.5
Jx17
in
.
light
alloy

"
Front
and
rear
tire

1992-1997
.............
.
.
.
...
...
235/40
x
17
in
.

"
Front
tire
1998
only
......
...
.
.
.
...
225/45
x
17
in
.

"
Rear
tire
1998
only
.......
.
.
.
...
...
245/40
x
17
in
.

CAUTION-

In
en
emergency,
an
M3
front
wheel/tire
assembly
may
be
mounted
on
the
rearaxle
.
However
a
rear
wheel/tire
assemblymust
not
be
mounted
on
the
front
axle
.

M3
RearSuspensionImprovements

"
Reinforced
trailing
arms
.

"
Recalibrated
shock
absorbers,
firmer
springs
.



SUSPENSION
AND
STEERING

TROUBLESHOOTING

Stable
handling
and
ride
comfort
both
depend
on
the
integ-

rity
of
the
suspension
and
steering
components
.
Any
symp-

tom
of
instability
or
imprecise
road
feel
may
be
caused
by

worn
or
damaged
suspension
components
.

When
troubleshooting
suspension
and
steering
problems,

also
consider
the
condition
of
tires,
wheels,
and
their
align-

ment
.
Tire
wear
and
incorrect
inflation
pressures
can
dramati-

cally
affect
handling
.
Subtie
irregularities
in
wheel
alignment

angles
also
affect
stabílity
.
Mixing
different
types
or
sizes
of

tires,
particularly
on
the
same
axle,
can
affect
alignment
and

may
unbalancea
car's
handling
.

Table
b
lists
the
symptoms
of
common
suspension
and

steering
problems
and
their
probable
causes,
and
suggests

corrective
actions
.
Bold
type
indicates
the
repair
groups

where
applicable
test
and
repair
procedures
can
befound
.

SUSPENSION
AND
STEERING
TROUBLESHOOTING

300-8



SUSPENSION,
STEERING
AND
BRAKES-GENERAL

Tableb
.
Suspension
and
Steering
Troubleshooting

Symptom



1



Probable
cause
Repairs
(Repair
Groups
shown
in
bold)

Car
pulís
to
one
side,
wanders



a
.
Incorrect
tire
pressure



a
.
Check
and
correct
tire
pressures
.
020
b
.
Incorrect
wheel
alignment



b
.
Check
and
adjust
wheel
alignment
.
320
c
.
Faulty
brakes
(pulls
only
when
braking)



I
c
.
Check
for
sticking/damaged
front
caliper
.
340

Steering
heavy,
poor
return-



a
.
Worn
upper
strut
bearing(s)



a
.
Replace
strut
bearings
.
310
to-center



b
.
Incorrect
tire
pressure



b
.
Check
and
correct
tire
pressures
.
020
c
.
Power
steering
system
faulty



c
.
Check
power
steering
fluid
level
.
Test
system
pressure
.
320

Front-end
or
rear-end
vibra-



a
.
Worn
strut
cartridgesor
shock
absorbers



a
.
Replace
strut
cartridges
.
310,
330
tion
or
shimmy



b
.
Worn
suspension
bushings
(control
arm
or
trail-



b
.
Replace
worn
bushings
.
310,
330
ing
arm)
c
.
Worn
front
suspension
ball
joints
(control
arm,



c
.
Replace
worn
ball
joints
.
310
steering
arm
orsteering
tie-rod
end)d
.
Unbalanced
or
bent
wheels/tires



d
.
Balance
tires
.
Check
tiresfor
uneven
wear
pat-
terns
.
Check
wheels
for
damage
.
e
.
Loose
wheel
lug
boits



e
.
Tighten
lug
boits
to
proper
torque
.

Poor
stability,
repeated
bounc-
I
a
.
Worn
strut
cartridgesor
shock
absorbers



I
a
.
Replace
strut
cartridges
.
310,
330
ing
after
bumps,
suspension
bottoms
outeasily

Suspension
noise
(especially



a
.
Worn
front
upper
strut
bearings



a
.
Replaceupper
strut
bearings
.
310
over
bumps)



b
.
Loose
front
strut
cartridge



b
.
Check/tighten
strut
cartridge
collar
nut
.
310
c
.
Worn
suspensionbushings
(control
arm
or
trail-



c
.
Replace
worn
bushings
.
310,
330
ing
arm)d
.
Worn
stabilizer
bar
rubber
mounts



d
.
Replace
stabilizer
bar
rubber
mounts
.
310,
330
e
.
Loose
suspension
crossmember



e
.
Check
crossmember
for
damage
.
Tighten
mounting
boits
.

Uneven
ride
height



a
.
Incorrect
coil
springs



a
.
Measure
ride
height
and
replacesprings
as
re-
quired
.
310,
330
b
.
Bent
or
damaged
suspension
components



b
.
Inspect,
repair/replace
asnecessary
.
310,
330
c
.
Sagging
coil
springs



c
.
Measure
ride
height
and
replace
springs
as
re-
quired
.
310,
330

Wheel
noise,
continuous



I
a
.
Worn
wheel
bearing



I
a
.
Replacewheel
bearing
.
310,
330
growling,
may
be
more
notíce-
able
when
turning

Steering
loose,
imprecise



a
.
Incorrect
tire
pressure



a
.
Check
and
correct
tire
pressures
.
020
-



b
.
Loose
steering
gearmounting
bolt(s)



b
.
Inspect
and
tighten
boits
.
320
c
.
Worn
tie
rodend(s)



c
.
Replace
tie
rod(s)
and
align
wheels
.
320
d
.
Faulty
front
wheel
bearing



d
.
Replace
wheel
bearing
.
310
e
.
Worn
or
damaged
steering
gear



e
.
Adjust
or
replace
steering
gear
.
320
f
.
Worn
tires



f
.
Replace
tires
.
010

SUSPENSION
AND
STEERING
TROUBLESHOOTING

Fig
.
8
.



Measuring
tie
rod
end
position
(for
reference
only)
.

3
.
Loosen
outer
tie
rod
end
lock
nut
.
See
Fig
.
9
.

Lock
nut

4
.
Unscrew
tie
rod
end
from
steering
gear
.

0012143

"
Make
sure
all
threaded
parts
are
clean
.
Replace
self-

locking
nuts
and
inner
tie
rod
lockplate
.
"
Install
outer
tie
rod
end
to
new
tie
rod
using
reference

measurement
recorded
earlier
.

Fig
.
9
.



Outer
tie
rod
end
lock
nut
(arrow)
.



"
Have
car
professionally
aligned
.

5
.
Installation
is
reverse
of
removal
.
Make
sure
all
thread-

ed
parts
are
clean
.
Have
thecar
professionally
aligned
.

Tightening
Torques

"
Outer
tie
rod
end
losteering
arm
....
45
Nm
(33
ft-Ib)

"
Outer
tie
rod
end
lock
nut
..
.......
.
35
Nm
(26
ft-Ib)

Tie
rod,
replacing

1
.
Raise
car,
remove
outer
tie
rod
end
ball
jointnut,
and

press
out
outer
tie
rod
end
ball
joint
as
described

above
.

2
.
Make
a
reference
measurement
of
outer
tie
rod
end
to

tie
rod
.
See
Fig
.
8
.
Record
measurement

NOTE-
Accurate
measuring
of
the
tía
rod
end
in
reference
to
the
tie
rod
will
help
to
approximate
wheel
alignment

when
new
parts
are
installed
.

STEERING
AND
WHEEL
ALIGNMENT



320-
5

3
.
Loosen
rack
boot
bellows
clamp
and
slide
bellows

back
.
Inspect
boot
for
any
signof
damage
.
Replace
if

necessary
.

4
.
Unlock
inner
tie
rod
end
lockplate
using
pliers
.

5
.
Using
special
tool,
unscrew
inner
tie
rod
end
from

steeringrack
.
See
Fig
.
10
.

WHEEL
ALIGNMENT

Caster
and
Camber

Fig
.
10
.
Special
tool
(arrow)
installed
on
inner
tie
rod
end
.

6
.
Installation
is
reverse
of
removal,
noting
the
following
:

Tightening
Torques

"
Outer
tie
rod
end
to
steering
arm
..
.
.
45
Nm
(33
ft-Ib)

"
Outer
tie
rod
end
lock
nut
..........
35
Nm
(26
ft-Ib)

"
Inner
tie
rod
to
steering
gear
.......
71
Nm
(52
ft-Ib)

Proper
handling,
stability,
tire
wear,
and
driving
ease
de-

pendupon
the
correct
alignment
of
al¡
four
wheels
.
The
front

axle
is
aligned
in
relation
to
the
rear
axie,
then
the
front
wheels

are
aligned
in
relation
to
one
another
.
This
is
known
as
a
four-

wheel
or
thrust-axis
alignment
.

The
BMW
E36
uses
a
sophisticated
multi-link
suspension

at
the
front
and
rear
of
the
car
.
Proper
alignment
requires

computerized
alignment
equipment
.

Front
and
rear
caster
and
Camber
are
both
fixed
by
the
de-

sign
of
the
car
.
Any
deviations
are
usually
the
result
of
worn
or

damaged
suspension
or
body
parts
.

WHEEL
ALIGNMENT

320-
6



STEERING
AND
WHEEL
ALIGNMENT

Front
Toe-in
andToe
Difference
Angle



Wheel
Alignment
Specifications

Toe-in
is
the
difference
in
the
distance
between
the
front
of



Alignment
specificationsfor
the
E36
are
listed
in
Table
a

the
front
wheels
and
the
rear
of
the
front
wheels
.
It
is
adjusted



and
Table
b
.
The
specifications
only
apply
under
the
following

by
altering
the
length
of
the
outer
tie
rods
.



conditions
:

Toe-in
adjustments
should
only
be
made
on
alignment
equipment
with
the
car
in
normalloaded
position
as
described

below
under
Wheel
Alignment
Specifications
.

Toe
difference
angledetermines
the
progressively
different

pathstaken
by
the
front
wheelsas
the
car
is
turning
.
It
is
fixed
by
the
steering
gear,
but
depends
on
accurate
setting
of
the
toe-in
.

Rear
Toe-in

There
is
no
provision
for
routinerear
wheel
toe-in
adjust-

ment
.
If
any
alignment
angles
deviate
from
specifications,
carefully
inspect
the
rear
trailing
arms,
rear
suspension
sub-
frame
and
al¡
associated
bushings
and
flexible
mounts
for
wear
or
damage
.
After
replacing
any
parts
that
appear
worn
or
damaged,
re-check
thetoe
measurements
.

WHEEL
ALIGNMENT

Table
a
.
Front
Wheel
Alignment
Specifications

"
Correct
wheels
and
tires
are
installed,
in
good
condition,
and
are
at
the
correct
inflation
pressures
.

"
Al¡
steering
and
suspension
parts
and
bushings
areun-

damaged
and
show
no
signs
of
abnormal
wear
.

"
Wheel
bearings
are
in
good
condition
.

"
Ride
height
is
in
accordance
with
specifications
.

See
310
Front
Suspension
and330
Rear
suspension
.

"
Car
isin
normal
loaded
position
.

Normal
loaded
position

"
Each
front
seat
.....:.............
68
Kg
(150
lb)

"
Rear
seat
(center)
................
68
Kg
(150
lb)

"
Trunk
.
.
.
..
.......................
21
Kg
(46
lb)

"
Fueltank
.
........................
...
.
..
..
full

3181325
Model



3181325



sport



M3
3
.0
liter



M3
3
.2
liter
suspension

Toe
angle
(total)



0°
18'±8'



0°
18'±8'



0°
10'
±5'



0°
10't5'

Camber

To
1995



-0°
40'±30'



-0°
58'±
30'



-0°55'±30'



-

1995
on



-0°
30'
±30'



-0°
51'±30'



-0°55'±30'



-0°
46'±30'

Caster

10°
wheel
lock



3°
41'±30'



3°
50'±30'



6°
38'±30'



9°
35'±30'

20°
wheel
lock



3°
52'±30'



3°
57'
t30'



6°
52'±30'



7°
50'±30'

Front
Wheel
Displacement



0°
t15'



0°t15'



0°
±15



0°
±15'

Table
b
.
Rear
Wheel
Alignment
Specifications

3181325
Model



3181325



sport



M3
3
.0
liter



M3
3
.2
liter
suspension

Toe
angle
(total)



0°
24't6'



0°
24'±6'



0'30'
.-t6'



0°
30't6'

Camber



-l'
40'
t15'



-2°
0'
t15'



-1
°
45'
t10'



-1'45'±10'

Maximum
allowabledeviation
between
sides



0°
±3'



0°
±3'



0°
t3'



0°
t3'

340-2
BRAKES

When
troubleshooting,
keep
in
mind
that
tire
inflation,
wear

and
temperature
can
affect
braking
and
suspension
.
See310

Front
Suspension
for
more
information
on
front
suspension

parts
inspection
.

Table
a
lists
symptoms
of
brake
problems,
their
probable

causes,
and
suggested
corrective
actions
.

Table
a
.
Brake
System
Troubleshooting

Symptom



1



Probable
cause



1



Repairs

Brake
squeal



a
.
Incorrectly
installed
brake
pads
or



a
.
Check
component
installation
.
parking
brake
shoes
b
.
Brakepad
carriers
dirty
or
corroded



b
.
Remove
brake
pads
and
clean
calipers
.
c
.
Brake
pad
anti-rattle
springs
faulty
or



c
.
Install/replace
anti-rattle
springs
.
missing
d
.
Brakepads
heat-glazed
or
oil-soaked



d
.
Replace
brake
pads
.
Clean
rotors
.
Replace
leaking
calipers
as
required
.
e
.
Wheel
bearings
worn
(noise
most



e
.
Replace
worn
bearings
.
See310
Front
Suspension
pronounced
when
turning)



or
330
Rear
Suspension
.

Pedal
goes
to
f
loor
when
braking



a
.
Brake
fluid
leve¡
low
due
to
system



a
.
Check
fluidlevel
and
inspect
hydraulic
system
for
leaks



signs
of
leakage
.
Fill
and
bleed
system
.
b
.
Master
cylinder
faulty



I
b
.
Replacemaster
cylinder
.

Low
pedal
after
system
bleeding



1
a
.
Master
cylinder
faulty



1
a
.
Replace
master
cylinder
.

Pedal
spongy
or
brakes
work
only



a
.
Air
in
brake
fluid



a
.
Bleedsystem
.
when
pedal
is
pumped



b
.
Master
cylinder
faulty
(interna¡
return



b
.
Replacemaster
cylinder
.
spring
weak)
c
.
Leaking
line
or
hose
unions



c
.
Repair
or
replace
lines
and
hoses
.
Bleed
system
.

Excessive
braking
effort



a
.
Brake
pads
wet



a
.
Use
light
pedal
pressure
to
dry
pads
while
driving
.
b
.
Brake
pads
heat-glazed
oroil-soaked



b
.
Replace
brake
pads
.
Clean
rotors
.
Replace
leaking
calipers
.
c
.
Vacuum
booster
or
vacuum
hose
con-



c
.
Inspect
vacuum
lines
.
Test
vacuum
booster
and
re
nections
to
booster
faulty



place
as
required
.
Test
vacuum
non-return
valve
for
one-way
air
flow
.

Brakes
pulsate,
chatter
or
grab



a
.
Warped
brake
rotors



a
.
Resurface
or
replace
rotors
.
b
.
Brake
padsworn



b
.
Replace
brake
pads
.
c
.
Brake
pads
heat-glazed
or
oil-soaked



c
.
Replace
brake
pads
.
Clean
rotors
.
Replace
leaking
calipers
.

Uneven
braking,
car
pulís
to
one



a
.
Incorrect
tire
pressures
or
worn
tires



a
.
Inspect
tire
condition
.
Check
and
correct
tire
pres-
side,
rear
brakes
lock



sures
.
b
.
Brake
pads
on
one
side
of
car
heat-



b
.
Replace
brake
pads
.
Clean
rotors
.
Replace
leaking
glazed
or
oil-soaked



calipers
.
c
.
Caliper
or
brake
pads
binding



c
.
Clean
and
recondition
brakes
.
d
.
Worn
suspension
components



d
.
Inspect
for
worn
or
damaged
suspension
compo-
nents
.
See
310
Front
Suspension
or
330
Rear
Sus-
pension
.

Brakes
drag,
bind
or
overheat



a
.
Brake
caliper
or
brake
pads
binding



a
.
Clean
or
replace
caliper
.(
b
.
Master
cylinder
faulty



b
.
Replacemaster
cylinder
.

WARNING
-

On
cars
with
All
Season
Traction
(AST),
special
BMW
service
equipment
is
required
to
properly
bleed
the
ABS/AST
system
.
For
safety
reasons,
the
brake
system
on
carswith
ABS/AST
must
not
be
bled
using
the
procedures
described
inthis
repair
group
.

BLEEDING
BRAKES

Brake
bleeding
is
usually
done
for
one
of
two
reasons
:
Ei-
ther
to
replace
oíd
brake
fluid
as
part
of
routine
maintenance
or
to
expel
trapped
air
in
the
system
that
resulted
from
open-
ingthe
brake
hydraulic
system
during
repairs
.

BLEEDING
BRAKES

Alwaysuse
new
brake
fluid
from
an
unopened
container
.It

is
important
to
bleed
the
entire
system
when
any
part
of
the

hydraulic
system
has
been
opened
.
On
cars
not
equipped
with
traction
control
(AST),
brake
system
bleeding
should
be

done
with
a
pressure
bleeder
.
On
cars
with
AST,
brake
bleed-

ing
should
be
done
by
an
authorized
BMW
dealer
.

WARNING
-

On
cars
with
All
Season
Traction
(AST),
special
BMW
service
equipment
is
requíred
to
properly
bleed
the
ABS/AST
system
.
For
safetyreasons,
the
brake
system
on
carswith
ABS/AST
must
not
be
bled
using
the
procedures
described
inthís
repair
group
.

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
.

340-
8
BRAKES

Fig
.
10
.
Brake
fluid
linesat
master
cylinder
(arrows)
.

6
.
If
fluid
reservoir
was
removed,
install
it
carefully
using
new
sealing
grommets
.

7
.
Mount
master
cylinder
to
brake
booster
using
a
new
0-
ring
and
new
self-locking
nuts
.

CAUTION-

Use
cave
not
to
over-torque
the
master
cylinder
mounting
nuts
.
This
could
damage
the
brake
booster
and
prevent
proper
vacuum
build-up
.

0012164

8
.
Connect
all
brake
fluid
lines
.
Connect
hydraulic
clutch
hose
to
brake
fluid
reservoir
.

9
.
Reconnect
fluid
leve¡
sender,
and
bleed
entire
brake
systemas
described
earlier
.

BRAKE
BOOSTER

BRAKE
BOOSTER

The
brake
booster
is
mounted
to
the
bulkhead
on
the
driver
sideofthe
engine
compartment,
directly
behind
the
brake
master
cylinder
.
See
Fig
.
11
.

0015225
Fig
.
11
.
Brake
booster
(arrow)
.
A
is
vacuum
hose
from
intake
mani-
fold
.
B
is
one-way
valve
.
Intake
manifold
vacuum
acts
ona
large
diaphragm
in
the
brake
booster
to
reducebrake
pedal
effort
.

Brake
booster,
removing
and
installing

1
.
Disconnect
negative
(-)
cable
from
battery
.

CAUTION-

Prior
to
disconnecting
the
battery,
read
the
battery
disconnection
cautions
given
at
the
front
of
this
manual
onpage
vi¡¡
.

Tightening
Torque

"
Brake
master
cylinder
to



2
.
Using
a
clean
syringe,
empty
brake
(luid
reservoir
.

brake
booster
.....
..
.
..
.........
26
Nm
(18
ft-Ib)



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



Brake
fluid
is
highly
corroslve
and
dangerous
to
the
environment
.
Dispose
of
it
properly
.

3
.
Remove
brake
fluid
level
sender
connector
from
reser-
voir
cap
.

4
.
Disconnectbrake
fluid
lines
from
master
cylinder
.
Plug
openings
.

5
.
Disconnect
engine
vacuum
hose
from
brake
booster
.