Q: What is an ARB Air Locker?
A: The ARB Air Locker is a replacement differential carrier that can either operate as a conventional differential, or lock both rear (or front) axle shafts together allowing maximum drive torque to be transmitted to both wheels. The locking function is controlled by the driver. Front axles can be locked when traversing slippery surfaces, giving maximum traction, then unlocked to regain full steering capability. As a safety feature, the front differential cannot be locked unless the rear differential has been first locked.
Q: What gear oil should I run with my ARB Air Locker
A: Any conventional or synthetic gear oil that is appropriate for your location and driving style. Stay away from anything that says “For Limit-Slip Diffs” or “Friction Modifiers”
Q: Gear oil is pumping out the top of my solenoid. What can I do to fix this?
A: First, we need to explain why this happens. All axles have breather hoses or caps to allow the internal pressure to be equalized with the outside air pressure. Pressure can build up inside the axle housing if these passageways are blocked, sealed, or stuck closed. The gear oil leaks past the o-rings in an attempt to expand and escape the axle. Given enough heat, time, and pressure a siphon is established and the gear oil will draw itself out the nylon air line. When the locker is not engaged, the solenoid is off and the valve closes the air tank to the air line. The gear oil is being pushed out the exhaust port, but cannot get into the compressor tank.
To address the issue, check your breather lines. Clear any clogs, gunk, or buildup you find. Small spring caps are notorious for getting covered in mud and staying closed. Replace these silly factory pieces with a true breather hose and accordion style expansion tubes. The idea is to facilitate pressure equalization and eliminate pressure build up.
Q: Gear oil is misting out the top of my solenoid when I disengage the locker. Is this normal?
A: Yes, it is normal. The o-rings are bathed in gear oil inside the axle. When the locker is disengaged, all the air pressure in the airline and the locker is being released. When air passes the lubricated o-rings, moisture is picked up and carried out with the air. This results in the slight misting.