Subaru Impreza 2004 User manual

FUJI HEAVY INDUSTRIES LTD. G1870GE5
2004 IMPREZA SERVICE MANUAL QUICK REFERENCE INDEX
CHASSIS SECTION
This service manual has been prepared
to provide SUBARU service personnel
with the necessary information and data
for the correct maintenance and repair
of SUBARU vehicles.
This manual includes the procedures
for maintenance, disassembling, reas-
sembling, inspection and adjustment of
components and diagnostics for guid-
ance of experienced mechanics.
Please peruse and utilize this manual
fully to ensure complete repair work for
satisfying our customers by keeping
their vehicle in optimum condition.
When replacement of parts during
repair work is needed, be sure to use
SUBARU genuine parts.
All information, illustration and specifi-
cations contained in this manual are
based on the latest product information
available at the time of publication
approval.
FRONT SUSPENSION FS
REAR SUSPENSION RS
WHEEL AND TIRE SYSTEM WT
DIFFERENTIALS DI
TRANSFER CASE TC
DRIVE SHAFT SYSTEM DS
ABS ABS
ABS (DIAGNOSTICS) ABS(diag)
BRAKE BR
PARKING BRAKE PB
POWER ASSISTED SYSTEM
(POWER STEERING) PS

FRONT SUSPENSION
FS
Page
1. General Description ....................................................................................2
2. Wheel Alignment .........................................................................................6
3. Front Transverse Link ...............................................................................15
4. Front Ball Joint ..........................................................................................18
5. Front Strut .................................................................................................19
6. Front Stabilizer ..........................................................................................23
7. Front Crossmember ..................................................................................24
8. Sub Frame ................................................................................................25
9. Front Support Arm.....................................................................................27
10. General Diagnostic Table..........................................................................28

FS-2
FRONT SUSPENSION
General Description
1. General Description
A: SPECIFICATIONS
*1 WRX: 20 mm (0.79 in)
STi: 19 mm (0.75 in)
*2 TS, GX: None
RS: 10 mm (0.39 in)
NOTE:
•Front and rear toe-ins and front camber can be
adjusted. If toe-in or camber tolerance exceeds
specifications, adjust toe-in and camber to the
specification.
•The other items indicated in the specification ta-
ble cannot be adjusted. If the other items exceeds
specifications, check suspension parts and con-
nections for deformities, and replace with new ones
as required.
Model Sedan Wagon OUTBACK
Non-turbo Turbo Non-turbo Turbo
Front
Camber (tolerance: ±0°45′)−0°15′−0°25′−0°10′−0°20′−0°05′
Caster 3°25′3°30′3°25′3°30′3°25′
Toe-in mm (in) 0±3 (0±0.12) Each toe angle: ±0°07′30″
Kingpin angle 14°20′14°35′13°30′13°45′13°20′
Wheel arch height
[tolerance:+12 -24 mm
(+0.47 -0.94 in)]
mm (in) 406
(15.98)
396
(15.59)
397
(15.28)
387
(15.24)
402
(15.83)
Diameter of stabilizer mm (in) 20 (0.79) *1 20 (0.79)
Rear
Camber (tolerance: ±0°45′)−1°25′−1°30′−1°15′−1°20′−1°10′
Toe-in mm (in) 0±3 (0±0.12) Each toe angle: ±0°09′
Thrust angle (Tolerance: ±0°30′) 0°
Wheel arch height
[tolerance:+12 −24 mm
(+0.47 −0.94 in)]
mm (in) 381
(15.0)
376
(14.80)
381
(15.0)
376
(14.80)
386
(15.20)
Diameter of stabilizer mm (in) *2 *1 —17
(0.67) —
(1) Front
A −B = Positive: Toe-in, Negative: Toe-out
α= Each toe angle
FS-00001
B
A
(1)

FS-3
FRONT SUSPENSION
General Description
B: COMPONENT
FS-00137
T8
T9
T3
(16)
(33)
(34)
(15)
(11)
(28)
(28)
(26)
(25)
(24)
(23)
(22)
(21)
(20)
(19)
(18)
(17)
(28)
(1) (2)
(5)
(4)
(3)
(6)
(28)
(7)
(8)
(9)
(27)
(10)
(28)
(28)
(28)
(4)
(11)
(8)
(31)
(9)
(27)
(28) (10)
(12)
(15)
(30)
(32)
(29)
(28)
(14)
(13) (12)
T11
T15
T14
T5 T12
T6
T6 T3
T9
T9
T10
T4
T13
T8
T1
T3
T3
T2
T2
T7
(28)
T10

FS-4
FRONT SUSPENSION
General Description
C: CAUTION
•Wear working clothing, including a cap, protec-
tive goggles, and protective shoes during opera-
tion.
•Before removal, installation or disassembly, be
sure to clarify the failure. Avoid unnecessary re-
moval, installation, disassembly, and replacement.
•Use SUBARU genuine grease etc. or the equiv-
alent. Do not mix grease etc. with that of another
grade or from other manufacturers.
•Before securing a part on a vise, place cushion-
ing material such as wood blocks, aluminum plate,
or shop cloth between the part and the vise.
•Be sure to tighten fasteners including bolts and
nuts to the specified torque.
•Place shop jacks or rigid racks at the specified
points.
(1) Front crossmember (18) Strut mount Tightening torque: N·m (kgf-m, ft-lb)
(2) Bolt ASSY (19) Spacer T1: 20 (2.0, 14.5)
(3) Housing (20) Upper spring seat T2: 25 (2.5, 18.1)
(4) Washer (21) Rubber seat T3: 30 (3.1, 22)
(5) Stopper rubber (Rear) (22) Dust cover T4: 34 (3.5, 25)
(6) Rear bushing (23) Helper T5: 40 (4.1, 30)
(7) Stopper rubber (Front) (24) Coil spring T6: 45 (4.6, 33)
(8) Ball joint (25) Damper strut T7: 50 (5.1, 37)
(9) Transverse link (26) Adjusting bolt T8: 55 (5.6, 41)
(10) Cotter pin (27) Castle nut T9: 70 (7.1, 52)
(11) Front bushing (28) Self-locking nut T10: 95 (9.7, 70)
(12) Stabilizer link (29) Sub frame T11: 105 (10.7, 77)
(13) Clamp (30) Cover T12: 155 (15.8, 114)
(14) Bushing (31) Boss T13: 175 (17.8, 129)
(15) Stabilizer (32) Clip T14: 186 (19.0, 137)
(16) Jack-up plate (33) Front support arm T15: 250 (25.5, 184)
(17) Dust seal (34) Sedan turbo model

FS-5
FRONT SUSPENSION
General Description
D: PREPARATION TOOL
1. SPECIAL TOOLS
2. GENERAL PURPOSE TOOLS
ILLUSTRATION TOOL NUMBER DESCRIPTION REMARKS
927380002 ADAPTER Used as an adapter for camber & caster gauge
when measuring camber and caster.
(1) 28199AC000 PLATE
(2) 28199AC010 BOLT
927680000 INSTALLER &
REMOVER SET
Used for replacing transverse link bushing.
927760000 STRUT MOUNT
SOCKET
Used for disassembling and assembling strut
and shock mount.
TOOL NAME REMARKS
Alignment gauge Used for wheel alignment measurement.
Turning radius gauge Used for wheel alignment measurement.
Toe-in gauge Used for toe-in measurement.
Dial gauge Used for damper strut measurement.
Coil spring compressor Used for strut disassembly/assembly.
(1)
(2)
ST-927380002
ST-927680000
ST-927760000

FS-6
FRONT SUSPENSION
Wheel Alignment
2. Wheel Alignment
A: INSPECTION
Check the following items before taking wheel alignment measurement.
Check items before taking wheel alignment measurement:
•tire air pressure
•unbalanced right and left tire wear, size difference
•tire run-out
•ball joint excessive play, wear
•tie rod end excessive play, wear
•wheel bearing excessive play
•right and left wheel base imbalance
•steering link part deformed, excessive play
•suspension part deformed, excessive play
Check, adjust and/or measure the wheel alignment in accordance with procedures indicated in the figure:
Wheel arch height (Front and rear)
<Ref. to FS-7, WHEEL ARCH HEIGHT, INSPECTION, Wheel Alignment.>
↓
Camber (Front and rear)
<Ref. to FS-8, CAMBER, INSPECTION, Wheel Alignment.>
↓
Caster (Front)
<Ref. to FS-9, CASTER, INSPECTION, Wheel Alignment.>
↓
Steering angle
<Ref. to FS-10, STEERING ANGLE, INSPECTION, Wheel Alignment.>
↓
Front wheel toe-in
<Ref. to FS-10, FRONT WHEEL TOE-IN, INSPECTION, Wheel Alignment.>
↓
Rear wheel toe-in
<Ref. to FS-11, REAR WHEEL TOE-IN, INSPECTION, Wheel Alignment.>
↓
Thrust angle
<Ref. to FS-13, THRUST ANGLE, INSPECTION, Wheel Alignment.>

FS-7
FRONT SUSPENSION
Wheel Alignment
1. WHEEL ARCH HEIGHT
1) Set the vehicle on a level surface.
2) Set the vehicle to “curb weight”conditions. (Empty luggage compartment, install spare tire, jack, service
tools, and top up fuel tank.)
3) Set the steering wheel in a straight line, then remove the vehicle straight ahead more than 5 m (16 ft) to
settle the suspension.
4) Suspend the thread from wheel arch (point “A”in figure below) to determine a point directly above center
of wheel.
5) Measure the distance between measuring point “A”and center of wheel.
(1) Wheel arch height (4) Front wheel arch height (7) Measuring point
(2) Front fender (5) Rear wheel arch height (8) End of spindle
(3) Rear quarter (6) Flange bend line
Model Specified wheel arch height mm (in) (tolerance: +12 −24 mm (+0.47 −0.94 in))
Non-turbo Turbo
Sedan Front 406 (15.98) 396 (15.59)
Rear 381 (15.0) 376 (14.80)
Wagon Front 397 (15.63) 387 (15.24)
Rear 381 (15.0) 376 (14.80)
OUTBACK Front 402 (15.83) —
Rear 386 (15.20) —
FS-00094
AA
A
(4)
(1)
(2) (3)
(1)
(5) (1)
(7)
(6)
(8)

FS-8
FRONT SUSPENSION
Wheel Alignment
2. CAMBER
•Inspection
1) Place the front wheel on turning radius gauge.
Make sure ground contacting surfaces of front and
rear wheels are set at the same height.
2) Set the ST into the center of wheel, and then in-
stall the wheel alignment gauge.
ST 927380002 ADAPTER
3) Follow the wheel alignment gauge operation
manual to measure camber angle.
•Front Camber Adjustment
1) When adjusting the camber, adjust it to the fol-
lowing value.
2) Loosen the two self-locking nuts located at lower
front portion of strut.
NOTE:
When adjusting bolt needs to be loosened or tight-
ened, hold its head with a wrench and turn self-
locking nut.
3) Turn the camber adjusting bolt so that camber is
set at the specification.
NOTE:
Moving the adjusting bolt by one scale graduation
changes camber by approx. 0°15′.
(1) Alignment gauge
(2) Turning radius gauge
Model Camber (Differences between
RH and LH: 45′or less)
Sedan Non-turbo −0°15′±0°45′
Turbo −0°25′±0°45′
Wagon Non-turbo −0°10′±0°45′
Turbo −0°20′±0°45′
OUTBACK −0°05′±0°45′
Model Camber (Differences between
RH and LH: 45′or less)
Sedan Non-turbo −0°15′±0°30′
Turbo −0°25′±0°30′
Wagon Non-turbo −0°10′±0°30′
Turbo −0°20′±0°30′
OUTBACK −0°05′±0°30′
FS-00007
(1)
(2)
ST
(1) Strut
(2) Adjusting bolt
(3) Housing
(4) Outer
(5) Inner
(6) Camber is increased.
(7) Camber is decreased.
(1)
(4)
(6) (7)
(2)
(3)
FS-00008
(5)

FS-9
FRONT SUSPENSION
Wheel Alignment
4) Tighten the new two self-locking nuts.
Tightening torque:
175 N·m (17.8 kgf-m, 129 ft-lb)
3. CASTER
•Inspection
1) Place the front wheel on turning radius gauge.
Make sure ground contacting surfaces of front and
rear wheels are set at the same height.
2) Set the ST into center of wheel, and then install
the wheel alignment gauge.
ST 927380002 ADAPTER
3) Follow the wheel alignment gauge operation
manual to measure caster angle.
Camber is increased.
Rotate camber adjusting bolt LH counterclockwise. Rotate camber adjusting bolt RH clockwise.
FS-00009 FS-00010
Camber is decreased.
Rotate camber adjusting bolt LH clockwise. Rotate camber adjusting bolt RH counterclockwise.
FS-00010 FS-00009
(1) Alignment gauge
(2) Turning radius gauge
Model Caster
Sedan Non-turbo 3°25′
Turbo 3°30′
Wagon Non-turbo 3°25′
Turbo 3°35′
OUTBACK 3°25′
FS-00007
(1)
(2)
ST