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Subaru Impreza 3 / Impreza WRX / Impreza WRX STI. Manual - part 497

DI-33

Rear Differential (T-type)

DIFFERENTIALS

2) Adjusting drive pinion height:

Adjust the drive pinion height with pinion height ad-

justing washer installed between the rear bearing

cone and the back of pinion gear.

(1) Attach the ST2.

NOTE:

At this time, install a provisionally selected or previ-

ously used pinion height adjusting washer. Mea-

sure and record the thickness.

ST1 398507702

DUMMY SHAFT

ST2 398507701

DIFFERENTIAL CARRIER

GAUGE

ST3 398507703

DUMMY COLLAR

(2) Measure the clearance “N” between the end

of ST2 and the end surface of ST1 by using a

thickness gauge.

NOTE:

Make sure there is no clearance between the differ-

ential carrier and ST2.

ST1 398507702

DUMMY SHAFT

ST2 398507701

DIFFERENTIAL CARRIER

GAUGE

(3) Obtain the thickness of pinion height adjust-

ing washer to be inserted from the following for-

mula, and replace the temporarily installed

washer with this one.

T = To + N – (H × 0.01) – 0.20 mm (0.0079 in)

(Example of calculation)

To = 3.39 mm (0.1335 in)

N = 0.24 mm (0.0094 in)

H = + 1

T = 3.39 mm (0.1335 in) + 0.24 mm (0.0094 in)

– 0.01 mm (0.0004 in) – 0.20 mm (0.0079 in) =

3.42 mm (0.1346 in)

Result: Thickness = 3.42 mm (0.1346 in)

Therefore use washer 383605200.

(A) Pinion height adjusting washer

DI-00083

(A)

ST2

ST3

ST1

DI-00084

ST2

ST1

Thickness of pinion height adjusting washer
mm (in)

Thickness of washer temporarily inserted mm
(in)

Clearance of thickness gauge mm (in)

Figure marked on drive pinion head

Memo:

Pinion height adjusting washer

Part No.

Thickness mm (in)

383495200

3.09 (0.1217)

383505200

3.12 (0.1228)

383515200

3.15 (0.1240)

383525200

3.18 (0.1252)

383535200

3.21 (0.1264)

383545200

3.24 (0.1276)

383555200

3.27 (0.1287)

383565200

3.30 (0.1299)

383575200

3.33 (0.1311)

383585200

3.36 (0.1323)

383595200

3.39 (0.1335)

383605200

3.42 (0.1346)

383615200

3.45 (0.1358)

383625200

3.48 (0.1370)

383635200

3.51 (0.1382)

383645200

3.54 (0.1394)

383655200

3.57 (0.1406)

383665200

3.60 (0.1417)

383675200

3.63 (0.1429)

383685200

3.66 (0.1441)

DI-34

Rear Differential (T-type)

DIFFERENTIALS

3) Install the selected pinion height adjusting wash-

er on drive pinion, and press the rear bearing cone

into position with ST.

ST 398177700

INSTALLER

4) Insert the drive pinion into the differential carrier,

and install the preselected preload adjusting spac-

er and washer.

5) Press-fit the front bearing cone with ST1, ST2

and ST3.

ST1 398507703

DUMMY COLLAR

ST2 399780104

WEIGHT

ST3 899580100

INSTALLER

6) Insert the spacer, then press-fit the pilot bearing

with ST1 and ST2.
NOTE:

Use a new pilot bearing.

ST1 399780104

WEIGHT

ST2 899580100

INSTALLER

7) Using the ST, install the oil seal.
NOTE:

• Use a new oil seal.

• Press-fit until the oil seal end comes 1 mm (0.04

in) inward from end of carrier.

• Apply differential gear oil to the oil seal lips.

ST 498447120

INSTALLER

8) Press-fit the companion flange with ST1 and

ST2.
NOTE:

Be careful not to damage the bearing.

ST1 899874100

INSTALLER

ST2 399780104

WEIGHT

(A) Drive pinion
(B) Preload adjusting spacer

DI-00085

DI-00704

(A)

(B)

(C)

(D)

DI-00087

ST3

ST1

ST2

DI-00088

ST2

ST1

DI-00089

DI-00090

ST1

ST2

DI-35

Rear Differential (T-type)

DIFFERENTIALS

9) Apply seal material on the drive pinion shaft

thread and new self-locking nut seat.
Seal material:

THREE BOND 1324 (Part No. 004403042) or

equivalent

10) Attach the new self-locking nut and use the ST

to fix the companion flange in place, then tighten

the self-locking nut.
Tightening torque:

181.5 N·m (18.5 kgf-m, 133.9 ft-lb)

ST 498427200

FLANGE WRENCH

11) Check the initial torque or initial load.
Initial load:

18.1 — 38.8 N (1.8 — 4.0 kgf, 4.1 — 8.7 lbf)

Initial torque:

0.69 — 1.47 N·m (0.07 — 0.15 kgf-m, 0.51 —

1.08 ft-lb)

12) Assembling differential case

Install the side gears and pinion mate gears, with

their side gear thrust washers and pinion mate

shaft, into the differential case.
NOTE:

• Apply gear oil on both sides of the washer and on

the side gear shaft before installing.

• Insert the pinion mate shaft into the differential

case by aligning the lock pin holes.

(1) Measure the side gear backlash.

Side gear backlash:

0.10 — 0.20 mm (0.004 — 0.008 in)

DI-00091

DI-00715

DI-00481

DI-00686

DI-00240

DI-36

Rear Differential (T-type)

DIFFERENTIALS

(2) Adjust the backlash as specified by select-

ing side gear thrust washer.

(3) Check the condition of rotation after apply-

ing oil to the gear tooth surfaces and washer

surfaces.

(4) Drive the pinion shaft lock pin into the differ-

ential case.

NOTE:

Use a new pinion shaft lock pin.

ST1 899904100

STRAIGHT PIN REMOVER

13) Install the driven gear to the differential case.
NOTE:

• Before installing bolts, apply seal material to bolt

threads.
Seal material:

THREE BOND 1324 (Part No. 004403042) or

equivalent

• Make sure there is no clearance between the dif-

ferential case and driven gear.

• Tighten opposing bolts in order.
Tightening torque:

103 N·m (10.5 kgf-m, 76.0 ft-lb)

14) Using the ST, press-fit the side bearing cone to

the differential case.

ST 398487700

DRIFT

15) Using the ST, press-fit the side bearing outer

race to the side retainer.
CAUTION:

Make sure that the bearing outer races and

cones are properly assembled.

ST 398417700

DRIFT

16) Side retainer shim adjustment

(1) The hypoid driven gear backlash and side

bearing preload can be adjusted by the side re-

tainer shim thickness.

(2) Install the differential case assembly into dif-

ferential carrier in the reverse order of disas-

sembly.

NOTE:

Be careful not to hit the teeth of hypoid driven gear

against the differential carrier.

(3) Install the side retainer shim.

NOTE:

• Be careful not to mix up the side retainer shim

RH and LH.

• Replace broken or corroded side retainer shims

with a new part of the same thickness.

Side gear thrust washer

Part No.

Thickness mm (in)

383445201

0.75 — 0.80 (0.0295 — 0.0315)

383445202

0.80 — 0.85 (0.0315 — 0.0335)

383445203

0.85 — 0.90 (0.0335 — 0.0354)

DI-00068

DI-00095

Side retainer shim

Part No.

Thickness mm (in)

383475201

0.20 (0.0079)

383475202

0.25 (0.0098)

383475203

0.30 (0.0118)

383475204

0.40 (0.0157)

383475205

0.50 (0.0197)

DI-00324

DI-00065

Content .. 495 496 497 498 ..