ARB RD168 - Manual (Page 14)

3 Installing the Air Locker
12
NOTE : Make sure any grinding dust, filings or drill chips left
behind by cutting the drainage slots is completely
cleaned out of the housing.
F Check that the axle air vents are clear and working correctly.
3.2 Approximate Backlash Shimming
In order to reproduce a similar pre-load and ring and pinion backlash
in your Air Locker to that of your original differential, measurements
need to be taken so that a shim thickness can be calculated.
F Secure the original differential to a work bench.
F Remove the bolts that hold the ring gear in place.
F Using a plastic or copper hammer, tap in a circle around the ring
gear to separate it from the differential carrier.
Figure 5.
F Assemble the original bearing cup onto the cone of the right-hand
side of the original differential carrier.