3 installing the air locker, Mounting the ring gear – ARB RD74 User Manual
Page 11

3 Installing the Air Locker
9
3.1
Mounting the Ring Gear
 Remove the bolts that hold the ring gear in place. 
 Using a plastic or copper hammer, tap in a circle around the ring 
gear to separate it from the differential carrier.
Thoroughly clean any thread locking compound or other foreign
matter from the holes of the ring gear, the threads of the ring gear 
bolts, the mating surfaces of the ring gear and the Air Locker 
flange. 
HINT : Rubbing the ring gear mounting face with a flat oil
stone before installation will remove any high spots 
around the threads. 
Heat the ring gear to between 80 and 100
°C (175 - 212°F) in hot
water or in an oven to slightly expand the gear and facilitate 
assembly. 
NOTE : NEVER HEAT GEARS WITH A FLAME! This could
damage the hardened surface of the gear and result 
in premature wear or failure. 
 Dry the gear and tapped holes with compressed air (if wet). 
 Apply a thin film of high-pressure grease to the ring gear shoulder 
of the Air Locker to prevent seizing.
Install the ring gear onto the Air Locker by aligning the tapped holes
and then gently tapping it around in a circle with a soft mallet or 
hammer. Avoid using the bolts to pull the ring gear down as this 
puts excess strain on the bolts and the differential flange. 
Apply a thread locking compound to the thread of each ring gear
bolt before inserting it. Do not apply locking compound directly into 
the threaded hole as this could prevent the bolt from reaching its 
full depth. 
NOTE :
On some models, the crown wheel bolts cannot be 
reused and should therefore be replaced. Refer to 
your vehicle manufacturer’s service manual for 
details. 
Tighten the ring gear bolts in a star pattern with a torque wrench
(Fig.4.) set to your vehicle manufacturer’s specified torque.
