Locking hubs

Locking hubs, also known as free wheeling hubs are fitted to some (mainly older) four-wheel drive vehicles, allowing the front wheels to rotate freely when disconnected (unlocked) from the front axle.

The benefits of unlocking hubs for normal road use are mainly found in increased fuel efficiency.

However, many manufacturers list engaging the hubs (even in 2WD mode) for several miles a month to lubricate the front drive train as part of the vehicle's regular maintenance schedule.

The advantage to mechanical hubs is that they are often considered more robust, and less prone to issues due to maintenance negligence.

The main advantage is that the driver does not need to leave the vehicle to connect the wheels to the axle.