Air lockers are one of the most popular types of selectable diff lockers used in off-road vehicles.
Unlike automatic lockers that engage on their own, air lockers allow the driver to lock and unlock the differential on demand using compressed air.
This gives the driver full control over when the differential is locked, allowing normal diff operation during everyday driving and maximum traction when it is needed off-road.
Air lockers are primarily used in four-wheel-drive vehicles, particularly those built for serious off-road use.
How an Air Locker Works
An air locker uses compressed air to engage a locking mechanism inside the differential.
Inside the diff centre is a locking collar that can slide across and connect the side gears to the carrier.
When the locker is not engaged, the differential operates normally, allowing the wheels to rotate at different speeds when the vehicle turns.
When the driver activates the locker, compressed air is sent into the differential through an air line connected to a small internal air piston.
The air pressure moves the piston, which slides the locking collar into position.
Once engaged, the collar locks the differential gears together, forcing both axle shafts to rotate at the same speed.
When the air pressure is released, the locking mechanism disengages and the differential returns to normal operation.
Common Air Locker Brands
Some of the most common air locker brands include:
• ARB Air Locker
• TJM Pro Locker
• Yukon Zip Locker
• HF Air lockers
Some air locker brands are supplied differently depending on the manufacturer.
Certain kits may include components such as:
• Air compressors
• Air lines and fittings
• Solenoids
• Wiring looms and switches
while others may require some of these parts to be purchased separately.
Advantages of Air Lockers
Driver Control:
The locker can be engaged only when needed, allowing normal differential operation during everyday driving.
Maximum Traction:
When engaged, an air locker provides 100% locking between both wheels.
Strength:
Air lockers are designed for heavy off-road use and are built with strong internal components.
Potential Limitations
Air lockers require additional components compared with other locker types, including:
- Air compressors
- Air lines that can leak when seal surfaces are worn or lines damaged by rough terrain
- Electrical switches and wiring
Because of this, the system requires proper installation and maintenance to ensure reliable operation.
Vehicles Commonly Fitted With Air Lockers
Air lockers are commonly installed in many popular off-road vehicles including:
- Toyota Hilux
- Toyota Land Cruiser
- Nissan Patrol
- Ford Ranger
- Jeep Wrangler
Installation
Installing an air locker involves replacing the differential centre with the locker assembly and fitting the required air system components.
Proper installation is important to ensure correct differential setup andproper routing of air lines.
At Gearhead Diffs we supply and install differential lockers for a wide range of vehicles.
