Subaru Impreza 3 / Impreza WRX / Impreza WRX STI. Manual — part 409

5MT-57

Main Shaft Assembly for Single-Range

MANUAL TRANSMISSION AND DIFFERENTIAL

• When the ring inner surface is abnormally or par-

tially worn down.

• When the contact surface of the synchronizer

ring insert section is cracked or abnormally worn.

• If the gap between the end faces of the ring and

the gear splined part is excessively small, check

the clearance (A) while pressing the ring against

the cone.
Clearance (A):

0.5 mm (0.020 in) or more

Single cone

Double cone

• Apply gear oil to the cone of the gear and while

press-fitting the baulk ring, check there is no rota-

tion in the circumferential direction.

5) Shifting insert key

Replace the insert key if deformed, excessively

worn or defective in any way.

6) Oil seal

Replace the oil seal if the lip is deformed, hard-

ened, worn or defective in any way.

7) Coupling sleeve and synchronizer hub

• Check the slipping condition of the coupling

sleeve.

• Check the splines on the coupling sleeve and

synchronizer hub for wear.

8) O-ring

Replace the O-ring if the sealing face is deformed,

hardened, damaged, worn or defective in any way.

9) Gearshift mechanism

Repair or replace the gearshift mechanism if ex-

cessively worn, bent or defective in any way.

F: ADJUSTMENT

Selection of main shaft rear plate:

Measure the protrusion amount (A) of double taper

roller bearing from transmission main case surface,

and select a suitable plate in the following table.
NOTE:

Before measuring, tap the end of main shaft with a

plastic hammer lightly in order to make the clear-

ance zero between the main case surface and

moving flange of bearing.

MT-01673

(A)

MT-01674

(A)

Dimension (A)

mm (in)

Part No.

Mark

4.00 — 4.13

(0.1575 — 0.1626)

32294AA041

1

3.87 — 4.00

(0.1524 — 0.1575)

32294AA051

2

MT-01807

(A)

5MT-58

Drive Pinion Shaft Assembly

MANUAL TRANSMISSION AND DIFFERENTIAL

16.Drive Pinion Shaft Assembly

A: REMOVAL

1) Remove the manual transmission assembly

from the vehicle. <Ref. to 5MT-23, REMOVAL,

Manual Transmission Assembly.>

2) Remove the transfer case together with the ex-

tension case assembly. <Ref. to 5MT-35, REMOV-

AL, Transfer Case and Extension Case

Assembly.>

3) Remove the transmission case. <Ref. to 5MT-

49, REMOVAL, Transmission Case.>

4) Remove the drive pinion shaft assembly.
NOTE:

Use a hammer handle, etc. to remove if too tight.

B: INSTALLATION

1) Remove the front differential assembly.

2) Hypoid gear set match mark/No.: The number

(A) on top of the drive pinion, and the number on

the hypoid driven gear are set numbers for the two

gears. Use a pair having the same numbers.

The figure (B) below shows a number for shim ad-

justment. If no number is shown, the value is zero.

3) Place the drive pinion shaft assembly on trans-

mission main case RH without shim and tighten the

bearing mounting bolts.

4) Check and adjust the ST.

(1) Loosen the two bolts and adjust so that the

scale indicates 0.5 correctly when the plate end

and the scale end are on the same level.

(2) Tighten the two bolts.

ST 499917500

DRIVE PINION GAUGE

ASSY

5) Position the ST by inserting the knock pin of ST

into the knock hole of transmission case.

ST 499917500

DRIVE PINION GAUGE

ASSY

6) Slide the drive pinion gauge scale with finger tip

and read the value at the point where it matches

with the end face of drive pinion.

ST 499917500

DRIVE PINION GAUGE

ASSY

7) The thickness of shim shall be determined by

adding the value indicated on drive pinion to the

value indicated on the ST. (Add if the number on

drive pinion is prefixed by +, and subtract if the

number is prefixed by –.)

ST 499917500

DRIVE PINION GAUGE

ASSY

(A) Main shaft ASSY for single-range
(B) Drive pinion shaft ASSY

(A) Set number
(B) Number for shim adjustment

MT-00161

( A )

( B )

MT-00990

(A)

(B)

(A)

+0.1

(A) Plate
(B) Scale

(A) Adjust the clearance to zero without shim.

MT-00242

(A)

(B)

ST

MT-00243

(A)

ST

5MT-59

Drive Pinion Shaft Assembly

MANUAL TRANSMISSION AND DIFFERENTIAL

8) Select one to three shims in the following table

for the value determined as described above, and

take the shim(s) which thickness is closest to the

said value.

9) Install the front differential assembly. <Ref. to

5MT-69, INSTALLATION, Front Differential As-

sembly.>

10) Fit the transmission case knock pin to the

knock pin hole of the roller bearing and install the

drive pinion shaft assembly.

11) Install the main shaft assembly for single-

range. <Ref. to 5MT-53, INSTALLATION, Main

Shaft Assembly for Single-Range.>

12) Check each shifter fork. <Ref. to 5MT-81, IN-

SPECTION, Shifter Fork and Rod.>

13) Install the transmission case. <Ref. to 5MT-50,

INSTALLATION, Transmission Case.>

14) Install the transfer case together with the exten-

sion case assembly. <Ref. to 5MT-35, INSTALLA-

TION, Transfer Case and Extension Case

Assembly.>

15) Install the manual transmission assembly to the

vehicle. <Ref. to 5MT-26, INSTALLATION, Manual

Transmission Assembly.>

C: DISASSEMBLY

NOTE:

Attach a cloth to the end of driven shaft (on the fric-

tional side of the thrust needle bearing) to prevent

damage during disassembly or reassembly.

1) Flatten the tab of the lock nut. Remove the lock

nut with ST1, ST2 and ST3.

ST1 899884100

HOLDER

ST2 498427100

STOPPER

ST3 899988608

SOCKET WRENCH (27)

2) Draw out the drive pinion shaft from driven shaft.

Remove the differential bevel gear sleeve, adjust-

ing washer No. 1, adjusting washer No. 2, thrust

bearing, needle bearing and drive pinion collar.

Drive pinion shim

Part No.

Thickness mm (in)

32295AA031

0.150 (0.0059)

32295AA041

0.175 (0.0069)

32295AA051

0.200 (0.0079)

32295AA061

0.225 (0.0089)

32295AA071

0.250 (0.0098)

32295AA081

0.275 (0.0108)

32295AA091

0.300 (0.0118)

32295AA101

0.500 (0.0197)

(A) Differential bevel gear sleeve
(B) Adjusting washer No. 1 (25 × 37.5 × t)

(C) Thrust bearing (25 × 37.5 × 3)
(D) Adjusting washer No. 2 (25 × 37.5 × t)

(E) Needle bearing (25 × 30 × 20)

(F) Drive pinion collar

(G) Needle bearing (30 × 37 × 23)

(H) Thrust bearing (33 × 50 × 3)

MT-00244

ST1

ST2

ST3

MT-00245

( B )

( D )

( C )

( A )

( F )

( H )

( G )

( E )

5MT-60

Drive Pinion Shaft Assembly

MANUAL TRANSMISSION AND DIFFERENTIAL

3) Remove the roller bearing and washer using ST

and a press.

ST 498077000

REMOVER

4) Flatten the tab of the lock nut. Remove the lock

nut using ST1 and ST2.

ST1 499987300

SOCKET WRENCH (50)

ST2 899884100

HOLDER

5) Remove the 5th driven gear using ST.

ST 499857000

5TH DRIVEN GEAR REMOV-

ER

6) Remove the woodruff key.

7) Remove the double taper roller bearing and 3rd-

4th driven gear using ST1 and ST2.

ST1 499757002

INSTALLER

ST2 899714110

REMOVER

8) Remove the key.

9) Remove the 2nd driven gear, inner baulk ring,

synchro cone and outer baulk ring.

10) Remove the 1st driven gear, inner baulk ring,

synchro cone, outer baulk ring, 2nd gear bushing

and gear & hub assembly using ST1 and ST2.

MT-00246

ST

MT-00247

ST1

ST2

MT-00248

S T

(A) 2nd driven gear
(B) Synchro cone

(C) Inner baulk ring
(D) Outer baulk ring

(A) 1st driven gear
(B) Synchro cone

(C) Inner baulk ring
(D) Outer baulk ring

(E) Gear & hub ASSY

(F) 2nd gear bushing

MT-00249

ST1

ST2

(A)

(B)

(C)

(D)

MT-02396

MT-02397

(D)

(E)

(F)

(C)

(B)

(A)