Subaru XT 1988 Service Manual page 534

3-2 AUTOMATIC TRANSMISSION AND DIFFERENTIAL
Engine power is transmitted from the rear planetary carrier to
the reduction drive shaft and the reduction drive gear. In a
FWD vehicle, power is then transmitted to the final gear
through the reduction driven gear and drive pinion. In a 4WD
vehicle, power transmission to the front wheels is the same as
a FWD vehicle. Power to the rear wheels is transmitted from
the transfer cl utch hub, welded to the side of the reduction
drive gear, and passes through the transfer clutch (multi-plate
clutch), to the rear drive shaft
-+
propeller shaft
-+
rear differ-
ential
-+
rear wheel.
1) HYPOI D GEAR
3-6 Final Reduction Gears
The hypoid drive gear is mounted to the cast iron oil pump
housing by double taper roller bearings. The hypoid driven
gear and the differential are mounted to the differential case.
Both ends rotate and are supported by taper roller bearings in
the converter case.
Bolt
/ Oil pump housing
Oil seal holder
Lock washer
!
Transmission case
Reduction driven
gear
Fig. 31
Drive pinion
shaft
Lock nut
Bolt
Double taper roller bearing
Hypoid
drive gear
Lock nut
L3·612
The front end of the drive pinion shaft is supported by the
double-taper roller bearing on the oil pump housing. The rear
end is supported by two roller bearings on the transmission
case and extension case (rear case for FWD vehicle). The
double-taper roller bearing is preloaded by tightening the lock
nut to a specified torque via the collar. The tooth contact of
the hypoid gear is adjusted by changing the shim thickness
between the double-taper roller bearing flange and oil pump
housing.
2) DIFFERENTIAL GEAR
The rear end of the drive pinion shaft is spline-fitted to the
reduction driven gear, which is secured with a lock nut. The
external helical spline has a length, and the reduction driven
gear is force-fitted to this shaft end.
-------
2700 cc 1800 cc
No. of drive pinion shaft
10 10
teeth
No. of hypoid drive gear 37 39
Diameter of hypoid
mm (in)
170 (6.69) 170 (6.69)
drive gear
Hypoid offset mm (in) 23 (0.91) 23 (0.91)
20
Bolt
Pinion shaft
Fig. 32
Left-hand
differential case
Differential bevel pinion
L3-613