Clean air is important to any vehicle engine and one can only imagine the conditions a 4WD air system would be subject to when driven offroad. Harsh conditions such as driving deep through water crossings and driving on extremely dusty outback tracks will be detrimental to your engine without proper air filtration.
is quite simply a raised air intake system and allows the vehicle to be completely submerged as long as the main intake is free of water. A snorkel
is highly recommended if you intend to travel in the outback. Beside creek and river crossings, heavy rains or flooding can be a constant threat and roads could become underwater in considerably short periods of time.
Snorkels can protect the engine from dust because air that is drawn from the roof level does not have as much dust content as in the air lower to the ground. This results in a cooler and cleaner air intake, which will also prolong the life of the air filtration system.