Subaru Impreza 3 / Impreza WRX / Impreza WRX STI. Service manual — part 489

DIFFERENTIALS

DI

Page

1.

General Description . . . . . . . . . . . . . . . . . . . . ...2

2.

Differential Gear Oil . . . . . . . . . . . . . . . . . . . . ..18

3.

Front Differential Assembly . . . . . . . . . . . . . . . . . ..21

4.

Rear Differential (T-type) . . . . . . . . . . . . . . . . . . ..22

5.

Rear Differential Front Oil Seal . . . . . . . . . . . . . . . . 54

6.

Rear Differential Side Oil Seal . . . . . . . . . . . . . . . . .56

7.

Rear Differential Front Member . . . . . . . . . . . . . . . . 57

8.

Rear Differential Mount Bushing . . . . . . . . . . . . . . . ..58

9.

General Diagnostic Table . . . . . . . . . . . . . . . . . . .62

DI-2

General Description

DIFFERENTIALS

1. General Description

A: SPECIFICATION

1. REAR DIFFERENTIAL

When replacing a rear differential assembly, select the correct one according to the following table.
NOTE:

Using a different rear differential assembly will cause the drive train and tires to drag or emit abnormal noise.

2. IDENTIFICATION

Identification positions are shown in the following

figures. For details concerning identification, refer

to the “ID” section.

3. REAR DIFFERENTIAL GEAR OIL

Recommended gear oil:

GL-5 (75W-90)

Alternative:

Equivalent product

CAUTION:

• If an alternative product is used, you may not

have expected functionality and performance.

• Each oil manufacturer has its base oil and ad-

ditives. Thus, do not mix two or more brands.

Model

2.5 L high power turbo

2.5 L turbo

6MT

5MT

Rear differential type

T-type

Identification

H3

B2

LSD type

Torsen

—

Type of gear

Hypoid gear

Gear ratio (Number of gear teeth)

3.545 (39/11)

3.900 (39/10)

Oil capacity

1.0 L (1.1 US qt, 0.9 Imp qt)

0.8 L (0.8 US qt, 0.7 Imp qt)

Rear differential gear oil

GL-5

(1) Identification

(1)

DI-00502

(1) Item
(2) Rear differential gear oil
(3) API classification
(4) SAE viscosity No. and applicable temperature

(1)

(4)

GL-5

(3)

(2)

( C)
( F)

-30

-15

15

90

75W -90

30

0

-22

32

86

59

5

MT-03000

DI-3

General Description

DIFFERENTIALS

4. SERVICE DATA

5. ADJUSTING PARTS

• T-type (B2)

Drive pinion bearing
preload (For new
bearing)

Measured with spring measurement (Measured at
companion flange bolt hole) N (kgf, lbf)

T-type (B2)

18.1 — 38.8 (1.8 — 4.0, 4.1 — 8.7)

T-type (H3)

24.1 — 38.6 (2.5 — 3.9, 5.4 — 8.7)

Measured with torque wrench N·m (kgf-m, ft-lb)

T-type (B2) 0.69 — 1.47 (0.07 — 0.15, 0.51 — 1.08)
T-type (H3) 0.98 — 1.57 (0.10 — 0.16, 0.72 — 1.16)

Side gear backlash

mm (in) T-type (B2)

0.10 — 0.20 (0.004 — 0.008)

Side bearing standard width

mm (in)

20.00 (0.7874)

Hypoid driven gear to drive pinion backlash

mm (in)

0.10 — 0.20 (0.004 — 0.008)

Hypoid driven gear runout on its back surface

mm (in)

0.05 (0.002)

Companion flange mating surface runout

mm (in)

0.08 (0.003)

Companion flange runout on its inner surface

mm (in)

0.08 (0.003)

Total preload (Measured from the companion flange bolt
hole)

N (kgf, lbf)

T-type (B2)

20.7 — 54.4 (2.1 — 5.5, 4.7 — 12.2)

T-type (H3)

26.5 — 53 (2.7 — 5.4, 6.0 — 11.9)

Part No.

Length mm (in)

Preload adjusting spacer

383695201

56.2 (2.213)

383695202

56.4 (2.220)

383695203

56.6 (2.228)

383695204

56.8 (2.236)

383695205

57.0 (2.244)

383695206

57.2 (2.252)

Part No.

Thickness mm (in)

Preload adjusting washer

383705200

2.59 (0.1020)

383715200

2.57 (0.1012)

383725200

2.55 (0.1004)

383735200

2.53 (0.0996)

383745200

2.51 (0.0988)

383755200

2.49 (0.0980)

383765200

2.47 (0.0972)

383775200

2.45 (0.0965)

383785200

2.43 (0.0957)

383795200

2.41 (0.0949)

383805200

2.39 (0.0941)

383815200

2.37 (0.0933)

383825200

2.35 (0.0925)

383835200

2.33 (0.0917)

383845200

2.31 (0.0909)

DI-4

General Description

DIFFERENTIALS

Pinion height adjusting washer

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)

Side gear thrust washer

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)

Side retainer shim

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)

Part No.

Thickness mm (in)