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This is from 4xforum.co.za about driving in sand
SAND DUNES
Driving on sand dunes is a particularly delicate conservation issue and should never be undertaken in a thoughtless manner. If driving up and over a dune, check over the top for people, other vehicles and the sharpness of the descent on the other side. Momentum is the single most important aspect when dune driving and everything a driver does must be geared to maintaining it - no matter how the conditions vary. When a vehicle is on hard ground between dunes the correct speed and gear ratio for the climb must be established. In most dune conditions high (normal) ratio first, second and even third gears are appropriate. Avoid changing gear mid-slope as in most cases it will degrade the vehicle’s momentum enough to stop it completely.
Gear selection in dune driving is, like all off-road driving, crucial. If you are using high-range first successfully, but occasionally need a lower gear to start off, use third, fourth and fifth low-range.
All rules have their exceptions. In 1996 a group of friends in a Hilux and my family in a Land Cruiser went exploring the NamibRand Nature Reserve in Namibia, where we found some exhilarating dune driving. On one particularly long steep climb the Hilux in front balked at the steep dune and came to a halt. After about eight attempts the driver had run out of options and the dune remained unconquered. Approximately two thirds of the way up there was a length of corrugations where the track became a little steeper. The corrugations were created by drivers hitting the accelerator at the base of the gradient increase. Acceleration here simply meant spinning wheels, loss of momentum and the resultant corrugations. I then asked if I could give it a go. On the early part of the slope I realised that flat out in second gear high-range was not going to give me enough momentum to overcome the difficult patch and I was unable to back up further to give me extra speed. So, when I reached the corrugations, at the moment when my wheels would start to spin, I changed into first gear and powered my way up the final 30 metres to the top. My friend, now in the Land Cruiser, with much more power and momentum at his disposal, did the entire climb in second. In situations like this a gear change may be required and vehicles with more power require less effort to drive.
Rules of dune driving:
Deflate tyres before dune driving.
Keep power constant on the slope.
Maintain the momentum of your vehicle.
You must aim to stop at the crest in order to inspect the descent and to engage the correct gear for the descent. The aim is to get your vehicle to stop at the top, even if it means touching the sand under its belly. Ideally its nose should be over the edge and the vehicle lying horizontal or pointing slightly downhill.
If it is pointing uphill you may need to go back down and try again.
You will need to decelerate as you near the top and judge it perfectly to get it right. If you stop and are still pointing uphill you will have to reverse back down and try again. Do this once you have checked the gradient and know what you are up against. Once your vehicle is successfully perched at the top, the next step is to dig away the crest that is touching the chassis between the wheels. Survey the drop and engage the low-range first for the descent. Keep your feet off the pedals and begin the descent. If the vehicle starts to slide sideways, steer towards the slide and apply gentle accelerator.
Side slopes on sand
Never attempt to go sideways when ascending or descending a dune, because if you do the lower wheels will dig in and your vehicle will roll. Loaded roof racks are ill-advised when dune driving, and a conscious effort should be made to keep the vehicle’s centre of gravity as low as possible when loading your vehicle. That will make dune driving safer. If the track ahead runs for a short distance along the side of a dune where the vehicle may slide, power is the only thing that will prevent the rear wheels from breaking away and the vehicle stopping at a precarious angle. Keep the power on and keep moving. If the back breaks away turn into the slope (downhill) and keep the power on. Getting stuck on a side slope is often a dangerous situation and the first priority should be to secure the front of the vehicle to prevent it from sliding any further and increasing the angle and the risk of rolling the vehicle.
SAND TRACKS
When driving on thick sand tracks engage four-wheel drive even if you do not require it. Tyre wear will be reduced and vehicle control will be easier. Fuel consumption will also be improved because, even if you don’t realise it, in two-wheel drive wheel spin will occur over the bumpy patches and speed is lost. The proof of this is the effect that a two-wheel drive has on this type of road. The spinning rear wheels cause large waves of sand to be built up and, after a time, driving on these roads is like riding a roller coaster.
When driving along deep sand tracks there is a natural tendency to fight with the steering wheel. This is due to the wheels sliding over the sand with very little feel being transmitted back to the driver as to which way the front wheels are pointing. Deep tracks can be driven without a hand being placed on the steering wheel at all. But don’t be fooled by this, as I once was and played a game of chance along the narrow sand tracks in the Kalahari - many 4x4s have come to grief as the front wheels spin out and the vehicle suddenly rolls over. On this type of track the vehicle moves as if it were on rails and the inexperienced driver will tend to fight the steering wheel and most of the time the front wheels will not be pointing in the direction of travel - the front wheels will plough through the sand, absorbing power and consuming excess fuel. Very little steering effort is needed to guide a vehicle in these conditions. Let the vehicle steer itself while holding the wheel firmly enough to catch it if it suddenly swings, gently coaxing the vehicle in the direction you wish to go.
When driving along tracks through thick bush it is important to keep the windows rolled up to eye height. This is done to prevent branches along the edges of bush tracks from whipping into the passing vehicle and causing injury to the occupants’ eyes.
Sand tracks that have very high walls are difficult to get out of.
To get out of the trough, decelerate lightly, swing the wheel over quite hard and then IMMEDIATELY SWING IT BACK to just off the dead ahead position. If the steering wheel is left in the hard over position, a slide and a roll-over could result. If it works, the vehicle’s front wheels will ride over the ridge and the rear wheels will follow. If it does not, centre the steering and try again. If you find it impossible to leave the track, as can sometimes happen, stop the vehicle and try it in reverse. If you are forced to leave the track due to an oncoming vehicle, stop and turn on your headlights. Try the reverse procedure pulling off to the left hand side of the track.
On two occasions I have come across a 4WD vehicle lying in the middle of a sand track on its side. On both occasions the driver had tried to get out of the track. He had swung the wheel hard over and when nothing happened he turned it even more. All of a sudden the front wheels had hit something solid and the vehicle left the track so sharply that it rolled over. This is a common occurrence. Don’t let it happen to you.
So remember:
Engage 4WD even if you don’t need it.
Hold the steering wheel gently.
Slow down well in advance when you see oncoming traffic.
BEACH DRIVING
Beach and sand driving have obvious similarities, but other important points should be considered when driving on the beach. Make sure you carry a can of Q-20, or a similar water repellent as well as a tyre gauge and pump with you. Drop tyre pressures before venturing onto the beach.
If the engine stalls or splutters because of water contaminating the electrical system, a dry rag and a spray of Q-20 in the distributor and on the HT lead connections is an instant cure. If you stall and are unable to restart, select 4WD low-range first gear and turn over the starter. Progress will be slow but if your battery has a good charge, you should be able to get out of reach of the waves. If the tide is threatening steer away from the water but remember that turning the steering to full lock will put a lot of resistance against the wheels and the starter motor may stall or the wheels may spin. If your tyres have a heavy tread, deflate them to as low as ten percent of normal road pressures.
An outgoing tide is the best time to drive on the beach due to the extra time to dig yourself out should you get into trouble. Do not underestimate the speed at which the tide comes in - you may lose your vehicle if you do! Drive as close as possible to the water’s edge without getting splashed and you will be driving on the firmest surface. Beware of shiny wet patches and keep them between you and the surf - they indicate deep patches of sand saturated with water. Areas of pebbles or shells which even under the best lighting conditions are difficult to detect, are treacherous. They are invisible when the sun is low in the sky. Avoid driving on an unfamiliar beach at night.
Driver techniques for beach driving vary, and the method described for sand driving works on the beach. Additional speed can be used due to the absence of obstacles (as long as there are no people about). There are no paths or roads on the beach so if there are other vehicles about, give way to anyone who appears to be having difficulty, and watch out for children.
Low gear ratios will induce wheel spin unless the driver is very careful about how he applies his right foot. For example, hitting the accelerator once in the difficult patch will immediately spin the wheels - and if you bog down after wheel spin, your vehicle will be much deeper than if you had simply run out of traction.
Another method is to ‘walk’ your vehicle by using low-ratio first gear and crawl through, never allowing your wheels to spin. When using this method there is always the temptation to race the engine and go a bit faster. Don’t be tempted - it’s an invitation to disaster!
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2004 KJ Sport 4x4
L.O.S.T. #006901
Rusty's 2.5" Coil Lift & Diff Skid, 245/75-16 REVO's, K&N
****Grocery Rated****
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It is pretty much flat the whole way but you sometime need to make the cross from the low road to the high road and that can be fairly challenging at times. And yes, the posted speed limit is dumb!
