Snorkel

What is a snorkel?

A pipe running from the factory air intake location up the A-pillar to an intake head above the roofline, replacing an intake opening that on most vehicles sits low, often behind the front bumper or inside the fender, right where dust thrown up by the front tires and any water crossing collects. ARB, a snorkel maker, states its own priority directly: a snorkel's primary function is to protect your engine from dust and dirt, with the ability to drive through deep water crossings named as the secondary benefit.

The two jobs work through different mechanisms. On dust, an intake at roughly head height sits above most of the dust cloud a vehicle stirs up at speed or in convoy, where a bumper-height intake sits inside it. On water, raising the intake raises the depth of water an engine can drive through before it draws water into a cylinder on the intake stroke, called hydrolocking, because water does not compress the way air does and something in the engine, usually a connecting rod, gives way instead.

What it does not do on its own

A snorkel only protects the air intake. Everything else that can drown in a water crossing, the alternator, the ECU, the differentials and their breather tubes, is untouched by fitting one, which is why a vehicle actually built for deep wading also gets extended breather hoses on the axles and transfer case, and sometimes a sealed alternator. A snorkel is one piece of a wading setup, not the whole thing, and marketing that leans on the fording depth number without mentioning the rest of that list is telling you a partial story.

The cooler-air horsepower claim some sellers make is the smaller of the two benefits and the hardest to measure on a given vehicle; the dust-protection claim is the one every source we found, manufacturer and user, agrees on without qualification.