ARB RD85 - Manual (Page 19)

4 Installing the Air Locker
17
4.5 Approximating the Backlash for Tube Position
If the backlash is not close enough to the specified amount, the tube
position cannot be accurately measured to modify the bearing cap for
tube clearance. This must be checked before hand.
c Set a depth indicator on one of the ring gear teeth as in figure 8.
c 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).
c Make sure backlash is less than 0.5mm.
NOTE : This backlash value is for the tube position only and
will not be used for final assembly.
Figure 8.
4.5.1 Re-Shimming the Backlash
NOTE : This step is only necessary when adjusting for
incorrect backlash.
c Remove the bearing cap.
c Spread the differential housing again (Refer to section 2.6).
c Remove the differential.
c To increase the amount of backlash, reduce the shim thickness ‘D’.
(Fig. 4.) and increase the shim thickness ‘E’ the same amount.
Reverse this step to decrease the backlash.
c Remount the differential as before.
c Release spreader tension.
c Re-check backlash.