water crossing for beginners


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You should have a snorkel fitted, don’t be mistaken for OEM raised air intakes as these will not help keep water out of your motor, check the height of the diff, transmission, gearbox and transfer case breathers these may need to be extended to keep water out

Unless you can easily see the crossings surface/ bottom you should always walk the intended line first, this will help you understand what the crossing surface/ bottom is made up of it will also reveal its depth and current strength, if you can’t walk it you should not drive it.

You should keep the manufactures wading depth in mind when evaluating if you should attempt the crossing, also keep in mind water above the window line is not advised not only will it probably make your 4wd float but will also be dangerous if you get stuck in the water

Your tyre air pressures should be adjusted to suit the crossing surface.

Once you are ready to make the crossing select low range 4wd ideally In 2nd gear for most 4wds as it will keep a good amount of momentum and reduce the chance of losing speed or staling while in the water, also engage your centre diff lock if you have one, Enter slowly at a consistent speed to avoid damaging your radiator or motor fan, once the front end is completely in the water slowly increase speed keeping RPMs About 2500 if you feel the vehicle losing speed gently press the accelerator to keep your momentum steady, do not change gears while in the water unless you have no other option, once you exit the water be sure to clear the exit prior to stopping

Safe Travels
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Before entering deep water, let your engine, diffs and axles cool down to avoid thermal shock.
If drum brakes are fitted and the crossing was deep enough to submerge the drum brakes, allow the brakes to dry after exiting the water before driving off.

John U

Well-Known Member
Great instructions so far.

If I could add, in addition to the excellent posts above, prepare for the worst, hope for the best. If you think there’s any chance you might need them, before you start the crossing, think about your recovery plan if everything goes wrong, install your winch isolator key and have your winch remote handy, connect tow straps so they’re ready to go if required. Rushing around trying to work this stuff out when the dung hits the fan can waste time and make things more dangerous.
Slow down. Panic is everyone’s enemy.
If you have one, a mate who’s raring ready to go into a cold stinky bog hole to help save your 4wd is worth their weight in gold.


Well-Known Member
Good advice. Not using high revs in water is important. You may have heard that sometimes the fan can hit the radiator during a crossing and damage them both. A common misconception is the the fan bends forward in the water. This is incorrect. When going through enough water, or too quickly, the gaps in and around the radiator fill with water, effectively sealing it off from the air. The fan blades then torque themselves forward in the vacuum which is created. Steady speed, steady revs, try to point downstream as much as possible. If you’ve bent your number plate forward, or lost it all together, you are crossing too quick.