ARB RD93 - Manual (Page 15)

3 Installing the Air Locker
13
Tap the hole from the outside using a ¼” NPT pipe tap.
Remove any sharp edges from the hole that may chip-off and fall
into the housing.
Carefully remove rags and inspect with a service light inside the
housing to insure no metal filings are left behind.
3.4 Setting the Backlash
Hold the bearing cups onto the Air Locker, insert it into the housing
and rotate it until it is fully in mesh with the pinion gear.
Sit the adjuster nuts into the threads against the bearing cups.
Install the bearing caps (use the markings from Section 2.4 to
determine which side is which) and hand tighten all bearing cap
bolts lightly.
Hand tighten both adjuster nuts against the Air Locker until only a
small amount of backlash can be felt.
Set a depth indicator on one of the ring gear teeth as in
Figure 8.
While supporting the pinion gear by holding the drive shaft, rotate
the differential in both directions while observing the maximum
variation in depth from the indicator (i.e., the highest value minus
the lowest value). This value is referred to as the ring and pinion
backlash.
Rotate the differential center 90
° and measure again for accuracy.
Figure 8.