Subaru Impreza 3 / Impreza WRX / Impreza WRX STI. Manual — part 495

DI-25

Rear Differential (T-type)

DIFFERENTIALS

7) Tighten the self-locking nut.
Tightening torque:

70 N·m (7.1 kgf-m, 51.6 ft-lb)

8) Attach the ST to rear differential.

ST 28099PA090 OIL SEAL PROTECTOR

9) Insert the spline shaft until the spline portion

comes inside the side oil seal.

10) Remove ST from rear differential.

11) Push the housing to fully insert the DOJ into the

rear differential.

12) Lower the transmission jack.

13) Installing procedure hereafter is in the reverse

order of removal.

14) After installing, fill the differential carrier with

gear oil up to the bottom of the filler plug or the oil

temperature switch hole. <Ref. to DI-19, RE-

PLACEMENT, Differential Gear Oil.>

15) Inspect the wheel alignment and adjust if nec-

essary.

C: DISASSEMBLY

1. T-TYPE (B2)

To detect the real cause of trouble, inspect the fol-

lowing items before disassembling.

• Tooth contact and backlash between hypoid

driven gear and drive pinion

• Hypoid driven gear runout on its back surface

• Total preload of drive pinion

1) Set the ST on vise and install the differential as-

sembly to ST.

ST 398217700

ATTACHMENT SET

2) Remove the air breather cap.
NOTE:

• Do not attempt to remove the air breather cap

unless necessary.

• Whenever the air breather cap is removed, re-

place it with a new part.

3) Remove the bolts, and then remove the rear

cover.

DI-00602

DI-00279

ST

DI-00280

DI-00518

(A) Air breather cap
(B) Rear cover

DI-00061

ST

(A)

(B)

DI-00672

DI-26

Rear Differential (T-type)

DIFFERENTIALS

4) Remove the side retainer attachment bolts, set

the ST to differential case, and extract the side re-

tainers RH and LH with a puller.
NOTE:

• Side retainer shim of each side should be kept

together with its mating retainer.

• Keep the side retainers separate by attaching

tags or in similar ways to make it possible to identify

RH and LH sides during reassembly.

ST 398457700

ATTACHMENT

5) Pull out the differential case assembly from the

differential carrier.
NOTE:

Be careful not to hit the teeth of hypoid driven gear

against the differential carrier.

6) Remove the oil seal and O-ring from the side re-

tainer.

7) When replacing the bearing race, remove the

bearing cup from the side retainer using ST.

ST 398527700

PULLER ASSY

8) Using the ST, remove the bearing cone.
NOTE:

• Do not attempt to disassemble the parts unless

necessary.

• Set the puller so that its claws catch the edge of

the bearing cone.

• Never mix up the RH and LH bearing races and

cones.

ST 18759AA000 PULLER ASSY

9) Remove the hypoid driven gear by loosening hy-

poid driven gear bolts.

10) Remove the pinion shaft lock pin from driven

gear side using ST.

ST 899904100

STRAIGHT PIN REMOVER

DI-00064

ST

DI-00065

DI-00066

ST

DI-00316

ST

DI-00068

DI-00701

ST

DI-27

Rear Differential (T-type)

DIFFERENTIALS

11) Draw out the pinion mate shaft, and remove

pinion mate gears, pinion mate gear washers, side

gears, and side gear thrust washers.
NOTE:

The gears and washers should be marked or kept

separately right and left, and front and rear.

12) Remove the self-locking nut while securing the

companion flange with ST.

ST 498427200

FLANGE WRENCH

13) Extract the companion flange with a puller.

14) Press the end of drive pinion shaft by using the

ST, and remove the drive pinion shaft, rear bearing

cone, preload adjusting spacer and washer.
NOTE:

Hold the drive pinion so as not to drop it.

ST 398467700

DRIFT

15) Remove the rear bearing cone from drive pin-

ion while supporting the cone with ST.
NOTE:

Place the replacer so that its center-recessed side

faces the bearing cone.

ST 398517700

REPLACER

16) Remove the front oil seal from differential carri-

er using ST.

ST 398527700

PULLER ASSY

(A) Side gear
(B) Pinion mate gear

(C) Side gear thrust washer
(D) Differential case

(E) Pinion mate shaft

(F) Pinion mate gear washer

(A) Companion flange
(B) Puller

DI-00685

(E)

(D)

(F)

(F)

(B)

(A)

(C)

(A)

(C)

DI-00071

ST

DI-00142

(B)

(A)

(A) Differential carrier
(B) Front oil seal

DI-00073

ST

DI-00074

ST

DI-00145

(B)

(A)

DI-28

Rear Differential (T-type)

DIFFERENTIALS

17) Remove the pilot bearing together with the front

bearing cone and spacer using the ST.

ST 398467700

DRIFT

18) When replacing the bearings, hit out the front

bearing race and rear bearing race in this order us-

ing a brass bar.

2. T-TYPE (H3)

To detect the real cause of trouble, inspect the fol-

lowing items before disassembling.

• Tooth contact and backlash between hypoid

driven gear and drive pinion

• Hypoid driven gear runout on its back surface

• Total preload of drive pinion

1) Set the ST on vise and install the differential as-

sembly to ST.

ST 398217700

ATTACHMENT SET

2) Remove the drain plug and oil temperature

switch, and drain the gear oil.
NOTE:

Remove the oil temperature switch and adapter as

a unit.

3) Remove the air breather cap.
NOTE:

• Do not attempt to remove the air breather cap

unless necessary.

• Whenever the air breather cap is removed, re-

place it with a new part.

4) Remove the bolts, and then remove the rear

cover.

(A) Pilot bearing
(B) Spacer

(C) Front bearing
(D) Rear bearing race

(A) 2 cutout portions along diagonal lines
(B) Tap alternately with brass bar.

DI-00076

ST

(B)

(A)

(C)

(D)

DI-00077

(B)

(A)

(A) Air breather cap
(B) Rear cover

(C) Oil temperature switch
(D) Drain plug

DI-00061

ST

DI-00678

(A)

(D)

(C)

(B)