Successful four wheel driving relies on a combination of knowledge and skill. An understanding of not only driving techniques for different conditions, but also the capabilities and limitations of your vehicle is critical. The final and crucial factor is your tyres.
On the Beach
Where possible, stay in high-range four wheel drive to maintain speed, but if you bog down, go into low range and try again.
Your driving depends on the sand conditions. Driving on hard packed sand can be very straightforward, but more often, beaches are windblown, with soft, traction sapping sand. This requires continual momentum, active throttle control being aware that high power could be necessary in certain soft and sand conditions with partially deflated tyres. (Absolute minimum pressure 1.1 bar or 16 psi).
Dropping pressure elongates the tyre's contact patch, creating better flotation through a wider footprint. Re-inflate the tyre as soon as possible after leaving the beach in your 4x4. Prior to this, drive at a maximum of 80km/h.
The most common 'mud negotiation' confronted by four wheel drivers is a boghole on a bush track - usually furrowed by massive wheelruts and axle-deep pits. Where possible, place the 4WD tyres on high ground to avoid dragging the diffs through the mud. If you slip off, keep the accelerator down and turn the steering wheel from side to side, enabling the side lugs of the tyres to gain grip on the side face of the ruts.
Check for buildup in the wheel arches. Clogged guards effectively eliminate any tread pattern on the tyres, so it is advisable to clean them out with a shovel where necessary.
Getting through mud requires momentum, so as a general rule, high range and full throttle is recommended.
Water crossings terrify novice 4x4 adventurers more than any other cross country circumstance.
The technique is simple. As with any unfamiliar crossing, walk the course first, taking note of any possible obstacles, and if necessary, marking their position. Select low range, and generally first gear. (It is not advisable with most 4WDs to change gear midstream, as water can get into the clutch plate).
After checking that your air intake is high enough to remain clear of water in the deepest section, set off, maintaining a steady speed to create a bow wave in front of the vehicle.
Because you can't see what the tyres are striking under the water, never reduce air pressure, and for the same reason, check for sidewall slashes or puncturing stakes after you've reached the other side.
The advantage of a 4WD in snow is that chains don't have to be fitted immediately. In light snow conditions, the idea is to break through the crust so the tyre tread can grip on the surface beneath.
Select high range and avoid acceleration surges and sudden braking. In deeper snow don't rev the engine, but go into low range and use minimal pressure to let the tyres bite rather than slip.
Never wrench the steering wheel sharply in snow - it could put you into a spin or a skid.
Not even the most capable 4WD, regardless of the tyres it's fitted with, can go through endless depths of deep snow without chains.
The most notorious challenge in the outback is bulldust. First instinct is to treat bulldust as if it were sand, but that can be a fatal mistake. Never deflate your tyres, for beneath the deep, powder-fine stretches of sand lies a rock hard base that pounds the chassis on impact and could split the sidewall of a partially inflated tyre.
Select high range and maintain a constant speed between 60 and 80km/h, correcting any sideways slews with both the steering wheel and more throttle.
The skill in tackling rocky conditions is to keep the tyres on the high ground all the time. This avoids 'high centering' (hanging the vehicle up on diffs, the transmission or bashplates).
Torque is more important than power in climbing rocky slopes, so select first or second gear low range to east the vehicle over any obstacles. Use minimal throttle openings to prevent tyre slip.
Where possible, stick to roadgoing tyre pressures, only dropping them when the vehicle is stuck and all other recovery techniques have failed. Although lower pressures maximise tyre footprint, they also increase the danger of pinching the tyre in a narrow crevice or slashing the sidewall on tree stakes or rocks.
In the Desert
While most of the techniques used in beach driving are applicable to desert treks, a fundamental different exists. With localised exceptions, Australia's deserts don't consist purely of sand but are a mix of sandridges interspersed with rocky depressions and flat spinifex or mulga country, meaning that tyres can very rarely be let down to coastal sand pressures for fear of staking. Maintaining momentum is crucial.
Don't fight the steering wheel. Rather, let the vehicle - within reason of course - find its own way, but take care on crests. If you find yourself running across the face of a dangerous slope, turn the wheels downhill and accelerate. This not only stops the vehicle from rolling over, but also restores steering capability and traction to the tyres.