Subaru Legacy (2005 year). Manual — part 663

5MT-99

MANUAL TRANSMISSION AND DIFFERENTIAL

General Diagnostic Table

2. DIFFERENTIAL

Symptom

Possible cause

Corrective action

1. Broken differential (case, gear, bear-
ing, etc.)
NOTE:
Noise will be developed and finally it will
become impossible to continue to run due
to broken pieces obstructing the gear rev-
olution.

(a) Insufficient or improper oil

Disassemble differential and replace bro-
ken components. At the same time check
other components for any trouble, and
replace if necessary.

(b) Use of vehicle under severe condi-
tions such as excessive load and
improper use of clutch

Readjust bearing preload and backlash
and face contact of gears.

(c) Improper adjustment of taper roller
bearing

Adjustment.

(d) Improper adjustment of drive pinion
and hypoid driven gear

Adjustment.

(e) Excessive backlash due to worn dif-
ferential side gear, washer or differential
pinion under severe operating conditions
of the vehicle.

Add recommended oil to the specified
level. Do not use vehicle under severe
operating conditions.

(f) Loose hypoid driven gear tightening
bolts

Tighten.

2. Differential and hypoid gear noises
Troubles of the differential and hypoid
gear always appear as noise problems.
Therefore noise is the first indication of
trouble. However noises from the engine,
muffler, tire, exhaust gas, bearing, body,
etc. are easily mistaken for the differential
noise. Pay special attention to the hypoid
gear noise because it is easily confused
with other gear noises. There are the fol-
lowing four kinds of noises.
• Gear noise when driving:
If noise increases as the vehicle speed
increases it may be due to insufficient
gear oil, incorrect gear engagement,
damaged gears, etc.
• Gear noise when coasting:
Damaged gears due to maladjusted bear-
ings and incorrect shim adjustment.
• Bearing noise when driving or coast-
ing:
Cracked, broken or rusty bearings
• Noise mainly when turning:
Noise occurs form differential side gear,
differential pinion or differential pinion
shaft, etc.

(a) Insufficient oil

Lubricate.

(b) Improper adjustment of hypoid driven
gear and drive pinion

Check tooth contact.

(c) Worn teeth of hypoid driven gear and
drive pinion

Replace as a set.
Readjust bearing preload.

(d) Loose roller bearing

Readjust hypoid driven gear to drive pin-
ion backlash and check tooth contact.

(e) Distorted hypoid driven gear or differ-
ential case

Replace.

(f) Worn washer and differential pinion
shaft

Replace.

5MT-100

MANUAL TRANSMISSION AND DIFFERENTIAL

General Diagnostic Table

MANUAL TRANSMISSION
AND DIFFERENTIAL

6MT

Page

1.

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

2.

Transmission Gear Oil . . . . . . . . . . . . . . . . . . . ..29

3.

Oil Seal. . . . . . . . . . . . . . . . . . . . . . . . . ..30

4.

Differential Side Retainer Oil Seal. . . . . . . . . . . . . . . .31

5.

Transmission Mounting System . . . . . . . . . . . . . . . . 32

6.

Manual Transmission Assembly . . . . . . . . . . . . . . . ...34

7.

Preparation for Overhaul. . . . . . . . . . . . . . . . . . ...40

8.

Air Breather Hose. . . . . . . . . . . . . . . . . . . . . ..41

9.

Oil Pipe. . . . . . . . . . . . . . . . . . . . . . . . . ..42

10.

Back-up Light Switch. . . . . . . . . . . . . . . . . . . . .43

11.

Neutral Position Switch . . . . . . . . . . . . . . . . . . . .45

12.

Extension Case . . . . . . . . . . . . . . . . . . . . . . .47

13.

Reverse Check System. . . . . . . . . . . . . . . . . . . .53

14.

Transfer Drive Gear . . . . . . . . . . . . . . . . . . . . ..56

15.

Transfer Driven Gear . . . . . . . . . . . . . . . . . . . . 58

16.

Center Differential . . . . . . . . . . . . . . . . . . . . . .60

17.

Oil Pump . . . . . . . . . . . . . . . . . . . . . . . . ...61

18.

Transmission Case . . . . . . . . . . . . . . . . . . . . ...64

19.

Main Shaft Assembly . . . . . . . . . . . . . . . . . . . . 69

20.

Driven Gear Assembly . . . . . . . . . . . . . . . . . . . ..83

21.

Reverse Idler Gear. . . . . . . . . . . . . . . . . . . . . 91

22.

Drive Pinion Shaft Assembly. . . . . . . . . . . . . . . . . .96

23.

Front Differential Assembly . . . . . . . . . . . . . . . . . .102

24.

Shifter Fork and Rod . . . . . . . . . . . . . . . . . . . ...110

25.

Clutch Housing. . . . . . . . . . . . . . . . . . . . . . 124

26.

General Diagnostic Table. . . . . . . . . . . . . . . . . . 126

6MT-2

MANUAL TRANSMISSION AND DIFFERENTIAL

General Description

1. General Description

A: SPECIFICATION

1. MANUAL TRANSMISSION AND FRONT DIFFERENTIAL

2. TRANSMISSION GEAR OIL

Recommended oil:

GL-5 or equivalent

Type

6-forward speeds and 1-reverse

Transmission gear ratio

1st

3.636

2nd

2.375

3rd

1.761

4th

1.346

5th

0.971

6th

0.756

Reverse

3.545

Front reduction
gear

Final

Type of gear

Hypoid

Gear ratio

3.900

Rear reduction
gear

Transfer

Type of gear

Helical

Gear ratio

1.100

Final

Type of gear

Hypoid

Gear ratio

3.545

Front differential

Type and number of gear

Straight bevel gear (Bevel pinion: 2, Bevel gear: 2)

Center Differential

Type and number of gear

Straight bevel gear

(Bevel pinion: 2, Bevel gear: 2 and viscous coupling)

Transmission gear oil

GL-5

Transmission gear oil capacity

4.1

2(4.3 US qt, 3.6 Imp qt)

(1) Item

(2) Transmission gear oil

(3) API standard

(4) SAE viscosity No. and applicable temperature

MT-00001

(1)

(4)

GL-5

(3)

(2)

( C)
( F)

-30 -26 -15

15

90

85W

80W

75W -90

25

30

-5 0

-22 -15

23 32

86

59

77

5