Toro Workman 3000 Series Service Manual page 417

When a change in backlash is required, backlash shims
should be changed in the range of 1-1/2 times the
amount of backlash required to bring the gears into
specification. For example, if the backlash needed to be
changed by .004", the shim pack should be changed by
.006" as a starting point.
High backlash is corrected by moving the ring gear clos-
er to the pinion. Low backlash is corrected by moving the
ring gear away from the pinion. These corrections are
made by switching shims from one side of the differential
case to the other.
Example 1: Backlash correct. Thicker pinion position
shims required (Fig. 64).
Example 2: Backlash correct. Thinner pinion position
shims required (Fig. 65).
Example 3: Backlash incorrect. Thinner pinion position
shim required. Adjust backlash to match (Fig. 66).
GEAR PATTERN MOVEMENT SUMMARY:
A. Decreasing backlash moves the ring gear closer
to the pinion.
Drive pattern (convex side of gear) moves lower
and toward the toe.
Coast pattern (concave side of gear) moves slight -
ly higher and toward the heel.
B. Increasing backlash moves the ring gear away
from the pinion.
Drive pattern (convex side of gear) moves higher
and toward the heel.
Coast pattern (concave side of gear) moves slight -
ly lower and toward the toe.
C. Thicker pinion position shim with the backlash
constant moves the pinion closer to the ring gear.
Drive pattern (convex side of gear) moves deeper
on the tooth (flank contact) and slightly toward the
toe.
Coast pattern (concave side of gear) moves deep -
er on the tooth and toward the heel.
D. Thinner pinion position shim with backlash
constant moves the pinion further from the ring gear.
Drive pattern (convex side of gear) moves toward
the top of the tooth (face contact) and toward the
heel.
Coast pattern (concave side of gear) moves to -
ward the top of the tooth (face contact) and toward
the heel.
Workman 4000 Series
RING GEAR
DRIVE SIDE
Heel
RING GEAR
DRIVE SIDE
Heel
RING GEAR
DRIVE SIDE
Heel
Page 10 – 31 Front Wheel Drive Section – 4WD (Rev. F)
RING GEAR
COAST SIDE
Toe Toe
Figure 64
RING GEAR
COAST SIDE
Toe Toe
Figure 65
RING GEAR
COAST SIDE
Toe Toe
Figure 66
Heel
Heel
Heel