Selectable Lockers:

What are selectable lockers? Selectable lockers are lockers that you can manually lock and unlock, allowing you to keep the benefits of an open differential when needed but also lock at the flip of a switch when you need more traction.

What different kinds of selectable lockers are there? The two most common types are Air Lockers and E-lockers or Electronic Lockers. Air lockers rely on an on-board air compressor to apply air pressure and lock the differentials, while E-lockers use electricity to activate electromagnets and lock the differentials. They replace the differential carrier like "full" automatic lockers, but can require some modifications of the axle housing itselft to allow power or air to get into the differential, this can make them the most expensive and difficult to install.

How do these benefit me? By putting you in complete control of the lockers, selectable lockers remove a little of the guess work as to when the lockers are going to engage or not, and allow you to be certain that you can get extra traction exactly when you need it. Similarly, since they don't engage without your input, they can be better in snowy areas where automatic lockers might lock when you don't want them to, and they can be totally unnoticeable on the road.

How can automatic lockers be better? Some people prefer not to have to worry about manually locking, and prefer to let automatic lockers simply take care of it for them. Selectable lockers are also usually the most expensive type of locker, especially if you need a compressor as well.

Any downsides? Since selectable lockers require an input, there's more to potentially go wrong, and if the power or air lines go bad you won't be able to lock at all. Because of this, Automatic Lockers can be a little less failure prone than selectable lockers, but any quality locker that is well installed should be reliable.