Selectable diff locker

There are three types of selectable lockers: air, electrical and mechanical. The former two can be locked with the push of a button.

An air locker works with a compressor that uses air to move a load plate that locks the differential gears so that your differential turns into a spool. A good example of this is the ARB Air Locker.

An advantage of ARB’s air locker is that you can use this compressor to inflate your vehicle’s tyres. However, one disadvantage is that the air hoses can spring a leak and then the diff won’t lock up.

An electric diff lock works the same except that it uses a 12 V electrical current to power an electromagnet or servo that moves the load plate to lock the differential. The Eaton ELocker is a well-known and reliable electric diff locker.

A disadvantage of the air and electric lockers is that they need a few seconds to engage, and you need to activate them before you hit an obstacle (not when you’re already in trouble). If these locks kick in while a wheel spins, you can also damage a side shaft or even break the diff, a phenomenon called crash lock.

Mechanical selectable lockers such as the Ox Locker work by pulling a short lever inside the cabin. A physical cable then moves the load plates within the differential and locks up the differential gears.

It’s a reliable type of selectable locker precisely because it is so simple.

Other benefits are that it locks immediately when you pull that lever – and stays locked regardless of power or air pressure.

There are those, however, who believe this direct link is too hard on the diff gears. Opponents of the mechanical selectable locker argue that the gradual and ‘soft’ coupling of an air or electrical locker is better.