ARB RD131 - Manual (Page 18)

4 Installing the Air Locker
16
4.7 Final Backlash Checking
Spread the differential housing again (Refer to section 2.6).
Hold shim packs ‘D’ (Refer to section 3.2) and ‘E’ (Refer to section
4.4) in position on the Air Locker.
Reinstall the Air Locker into the differential housing, ensuring that
the seal housing is positioned so that the tube will clear the bearing
cap.
NOTE : If the carrier is too difficult to install with the added
shim pack then the spreader tension may need to be
increased. Do not spread the housing more than
0.50mm [0.020”].
Place the bearing caps in place to align the seal housing.
Relieve all tension on the housing spreader.
Tighten all bearing cap bolts with a torque wrench to the torque
specified in your vehicle manufacturer’s service manual.
Set a depth indicator on one of the ring gear teeth as in Fig. 9.
While supporting the pinion gear by holding the drive flange, 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 9.
Refer to your vehicle service manual for the specified maximum
and minimum amounts of backlash. If the backlash is not within the
specifications then the differential will have to be removed and re-
shimmed.