Toro Groundsmaster 3280-D Service Manual page 410

Installing the Differential Gear Assembly (4-Wheel Drive Axle) (continued)
Drive Axles: Service and Repairs
1. If the ring gear was removed from the differential case, use medium strength
Loctite threadlocker and tighten the mounting screws to 30 to 34 N·m (22
to 25 ft-lb).
2. Apply molybdenum disulfide lubricant (Threebond 1901 or equivalent) to the
splines and bearing surfaces of the differential pinion gears, pinion washers,
and side gears.
3. Install the side gear shims and side gears in their original location in the
differential case.
4. Place the differential pinion gears and pinion washers in their original location
in the differential case. Temporarily install the differential pinion shaft.
5. Secure the differential case in a soft jawed vise. Position a dial indicator on a
tooth of the differential pinion gear. Press the pinion and side gear against
the differential case and measure the pinion gear to side gear backlash
(Figure 280).
Pinion gear to side gear backlash: 0.10 to 0.40 mm (0.004 to 0.016 inch)
6. Adjust backlash by increasing or reducing the side gear shim thickness.
Note: Side gear shims are available in 1.10 mm (0.043 inch), 1.20 mm
(0.047 inch), and 1.30 mm (0.051 inch) thickness.
7. Apply gear marking compound, such as DyKem steel blue lightly over
several gear teeth.
8. While applying a light load to either side gear, rotate either pinion gear until
the side gears have made 1 complete revolution.
g226499
1. More than 35% total tooth contact
9. Ideal tooth contact should cover more than 35% of each tooth surface. The
contact area should be in the center of each tooth and extend 1/3 to 1/2 way
across each tooth from the toe (small) end
10. Adjust the side gear shims if necessary to correct tooth contact. Check the
differential pinion gear to side gear backlash if any changes are made.
11. After backlash and tooth contact have been adjusted, align the hole in the
differential pinion shaft with the hole in the differential case and install a
new spring pin.
12. Install the differential gear assembly in the right side axle support half.
13. Coat a new O-ring with grease and install the left side axle support half.
Tighten the axle support case screws to 47 to 56 N·m (35 to 41 ft-lb).
14. Install the input shaft/pinion gear assembly; refer to the
Gear (4-Wheel Drive Axle) (page
Figure 281
2. 1/3 to 1/2 of entire width from small end
of tooth
8–61).
Page 8–68
(Figure 281).
Input Shaft/Pinion
Groundsmaster
05138SL Rev B
® 3280-D/3320