Snorkels for 4WD Vehicles/Water Blinds or Water Bra/Diff Breathers

All you need to know about vehicle snorkels and vehicle water crossing blinds (bras).
What is a diff breather and why do you need one?

Vehicle Snorkels

Vehicle engines run best on cool clean air and in most vehicles the air intake is located lower say behind the grill or through the inner guard of the bonnet of the vehicle.  Lower air intake areas are more susceptible to dust and although the air filter will trap most of the dust the filter will need regular changing or cleaning to maintain good engine performance.

Popular 4WD and RV destinations may require you to cross over streams and rivers.  If water is sucked through the air filter and into the vehicle engine it can cause a hydraulic lock.  Only a small amount of water ingested into a diesel engine, which has a high compression of about 20:1, can cause it to lock and cause major damage.  A petrol engine has a lower compression of about 10:1 but water can still cause serious damage.

The Safari snorkel air ram can be rotated to prevent dust ingress, say when travelling in a 4WD tag along tour or convoy, as well as when driving in heavy rain and snow.  The air ram should be rotated back to the forward position for normal driving as having it rotated backward can reduce performance. 

Safari Snorkel 7” or 10” Pre-Cleaner replaces the air ram head on Safari Snorkels and as air enters the round clear perspex chamber the dust particles are separated by centrifugal force.  The dirt then settles in the bottom of the outside chamber before it reaches your air filter.

Donaldson TopSpin air filters fitted to vehicle snorkels are also an alternative in dusty situations.  This filter increases the life of the vehicle's air filter by ejecting dust particles before they reach the air filter.

Uni Filter Australia supply a one size fits all Snorkel Ram Head Cover which they state provides a locust barrier and additional protection when in a 4WD convoy.  Uni Filter also supply a “Droopie” Snorkel Pre-Cleaner, a sock like sleeve that drops down from ram inside the snorkel, which they state does not affect air flow and removes 90% of dust before it reaches the main filter.  However, the Snorkel Pre Cleaner Service Instruction on their website contains the ‘Warning: Unifilter’s snorkel pre-cleaners are not suitable for highway use.  We recommend use only in dusty conditions”.  If your vehicle is a turbo diesel talk to a specialist before using these as they are coated in oil to collect the dust and the oil sucked into the turbo may cause problems.

Toyota Genuine Air Filters have a triple layer filtering element which has a series of different gauge meshes such as course, medium and fine to trap different size particles.  Toyota also manufacture a washable air filter or reusable air filter so if you have two you can swap over the spare and clean and wash the other out later. 

Popular brands of snorkels are Air Flow Gibson RM Snorkels, Airtec Snorkels and Safari Snorkels.

Where can I get a vehicle snorkel?

Vehicle snorkels are usually an aftermarket accessory and are available from Safari Snorkels, TJM, ARB, Opposite Lock and other 4WD accessory stores and eBay.

Step by step instructions on the installation of vehicle snorkels are available from some manufacturer’s and supplier’s websites.

Vehicle Water Crossing Bra or Water blind

If you are unable to afford a vehicle snorkel you could consider a water crossing bra or water crossing blind to straps over the front of your vehicle’s grill.  There are marine grade heavy duty, PVC backed water crossing bra that attach to the vehicle’s side rear view mirror mounts.  Three large gills at the base of the water crossing bra allow water to drain away after the crossing.  The front of the water crossing bra also has a built-in snatch strap pouch and will conform to any vehicle shape including those with winches and antennas. 

MSA Products (previously Michelle Sacs) make a product called a water crossing bra and this is available from them or 4WD after market suppliers such as ARB, TJM, Opposite Lock, BTA 4WD Centre, Active 4 x 4, Mannell Motors and Top Gear 4WD Centre.

Differential (Diff) Breathers

When attempting a creek or river crossing it is best to stop for a while to allow the differential to cool.  Differentials have a breather to equalize the pressure in the axle as the temperature in the axle changes.  The stock breather is a vent to the outside air with a cap over it to prevent debris and water.  When crossing creeks and the axle is submerged in cool water the temperature in the axle and the diff housing changes so when the axle is under water the change in pressure can pull water into the axle housing.

For those of you with some mechanical ability, extending the diff breather may be a relatively easy job.  You can do this by removing one of your diff breathers (these are a little plug screwed into the top of the differential), take the diff breather to someone who can make you up a hose fitting with the same thread as the breather.  Purchase some transmission cooler hose (as this type of hose is manufactured to be fuel and oil resistant) to suit the fitting as well as some small cable ties or electrical ties and then replace the factory breathers with the new fittings, run the hose to a high position under the bonnet keeping it away from heat.  Make sure you run the hose high to the top of the firewall and where it will not be subjected to impact. Leave enough slack in the hose for any diff drop and ensure the hose is positioned so there will be no cramping of the hose.  Another option, suggested on a 4WD forum, was to cut the hose endfitting (not the diff end) and buy 2 double ended barbs to fit inside the diameter of the diff hose.  Then insert one end of the double ended barb into the hose still attached to the diff and insert the extension hose onto the other end of the barb.  Use clamps to make sure the hose or breather lines don’t separate. The opinion on some forums is a filter is not required for the end of the diff breather hose but some have attached a lawn mower petrol filter to keep out dust.

Even when adding extended diff breathers it is still considered necessary to allow time for the diff to cool down before a creek crossing as there is no guarantee water will not enter the diff with a sudden reduction in air pressure.

Kits are available to extend the diff breathers higher up the chassis by using plastic tubing.  Diff breather kits are available from 4WD accessory stores and eBay.

There is also a product called Creeper Breather – Differential breather kit.  This kit includes a bellows, a housing fitting and clamp.  The Creeper Breather fits all Toyota Pick Up / 4Runner solid axle housings (front and rear).  Available from Trail-Gear.com or one of their distributors.