It happens to all of us once in a while. You’re driving along in your big 4X4 with a decent set of tyres and you’re overtaken by this yearning to veer off the beaten track and take to the hills. Let’s face it, it’s the natural thing to do. However off-road is no place to be if you don’t know how to handle yourself and your vehicle. There are several basic things you should be aware of before you set off.
For instance, understanding the difference between momentum and acceleration – momentum being the speed that the vehicle has already built up that allows you to go through that muddy patch or sand. Acceleration is what you use to build up that speed. What this means is don’t try to suddenly accelerate like mad when you hit that mud or sand If anything, this will only make sure that you get stuck. Rather build up the speed beforehand so that the momentum carries you through it.
DON’T FIGHT IT
As well as this there is our natural tendency to “fight” the vehicle. If you ever have the chance to watch vehicles driving through deep ruts in muddy terrain, notice the direction of the front wheels — very often they are pointing in a slightly different direction. When driving through demanding terrain, avoid the tendency to hold the steering wheel in a death grip — let the wheel move around and gently guide the vehicle. Releasing the wheel slightly allows the wheels to “centre”, ensuring that they are pointing in the right direction. Similarly, use gentle applications of the brakes and accelerator. This is especially important in sand driving.
And then there’s tyre pressure. Reducing tyre pressure increases the “flotation” of the vehicle. The tyre’s footprint becomes longer, reducing the pressure that the tyre exerts on the surface, spreading the vehicle’s weight over a larger surface. Reducing the tyres’ pressure will improve your traction, but remember that it will decrease your ground clearance and can expose the tyres’ sidewalls to damage in a rocky area.
It’s crucial that you get to know your vehicle inside out. Get down on your knees and look underneath. What are the lowest points, what could get damaged, how high is the air intake? Keep these in mind when driving off road.
Get a good, strong tow rope. It’s essential to help you navigate through any problems in which you find yourself. However, remember this piece of equipment is useless unless there’s another vehicle to attach it to. Never go off-road on your own.
When it comes to special vehicle modifications this is a highly debatable area. For every type of alteration, there’s a compromise that has to be made somewhere along the line. Tyres, for example. Changing to a more aggressive, off-road type tread pattern can affect the vehicle’s on-road handling and can have other side effects such as increased noise. Be honest with yourself about how you use your vehicle and modify it accordingly. The “Super Duper Extreme Mud Diggers” tyres may look cool but if 99% of your driving is on- road, they’ll be a large waste of money and cause you more irritation than pleasure.
There are several very different types of terrain you’ll encounter regularly. Basically they are sand, mud and deep water, but with a little pre-planning and common sense they shouldn’t cause the experienced driver any problems.
To begin with there’s sand driving. Choosing a gear that allows the engine to rev slightly high, allows you a safety margin in the event of deep patches. When you feel wheel-spin beginning, ease off on the accelerator; if you feel that you’re getting stuck, take your foot off the accelerator and coast to a stop. If you can, reverse; if not get some help. It’s no good trying to keep going as you’ll only get into deeper trouble and make any chance of recovery more difficult. Stopping using the brakes while driving In sand will cause small mounds to build up in front of the wheels. You should avoid using the brakes. Wherever possible, try to park the vehicle facing downhill as this will make pulling away easier. Sand driving is easier in the early morning due to the effect that the condensation has On the sand particles.
You can reduce your tyre pressure as low as 1,2 bar on 4×4 vehicles, however do bear in mind that any sudden turns may cause the tyre to roll off the rim. If your vehicle is fitted with a “diff lock”, be very careful when using this in sand as it can cause the vehicle to handle strangely. For instance, people often tend to forget that the “duff lock” is engaged and try to make a turn while the vehicle tries to keep going straight. The driver turns the steering wheel more until the point is reached where the sand that is building up on the outside of the front wheels suddenly causes the vehicle to turn. Vehicles can easily roll over even at incredibly low speeds due to this.
There will, however, be times when you will become stuck. The first thing to do is stop. Take some time to work out why you’re stuck. Dig away any sand in front of the wheels and place items such as car mats, branches etc. under the wheels that will give you traction Another tip to try should you become stuck in sand is to rock the car from side to side. This allows the sand to fall into the holes made by the wheels, slowly lifting the car out. As always, when you’re going off-road take along your tyre gauge and compressor (to re-inflate tyres), a shovel and your trusty tow rope.
Then there’s mud. Mud comes in various types, from thick, bottomless clay to the slippery surface mud found in forests. As with sand driving, the keys are reduced tyre pressures, a low gear to give enough engine speed, and momentum. Before you drive through any mud, take the time to look at the terrain and where you need to go. Better to get your shoes a bit dirty than just blasting into it and getting stuck. Look at the terrain around you — if it’s rocky, there’s a good chance that there’ll be rocks in the mud too.
There will, however, be times when you will become stuck. The first thing to do is stop. Take some time to work out why you’re stuck. Dig away any sand in front of the wheels and place items such as car mats, branches etc. under the wheels that will give you traction.
No matter how much you are tempted, don’t change gear, as you’ll reduce the momentum of your vehicle and probably become stuck.
If you feel any wheel-spin, try easing off the accelerator to slow down the wheels and give them a chance to get traction. Alternatively you can try to gently move the steering wheel from side to side to give the tyres’ sidewalls a chance to get a foothold. Don’t try to force the steering wheel in a particular direction, just hold the wheel gently and guide the vehicle in the direction that you want to go. Of course “duff locks” can help you to get through muddy patches, but as is the case with sand driving, they will tend to force the vehicle to go straight.
Should you become stuck in mud, stop and determine exactly why you are stuck. Getting unstuck normally involves digging. Clear mud away in front of the wheels and try to get branches or any other items that will give you traction under the wheels. Pulling away may also require some assistance in the form of a push or a tow rope. Useful tools to take along are a tyre gauge, compressor, decent tow rope and a spade (a shovel is extremely hard work in sand).
Water crossing can be a dangerous and often deceptive challenge. Again, a lot of problems can be avoided by knowing your vehicle: know how low your air intake is situated and let that guide you. For bakkies, as a rule of thumb, don’t try anything deeper than the top of your tyre. As you approach rivers, take in the surrounding terrain. Obviously, if the area around the river is rocky, there’s a good chance that there will be rocks in the river. There are several basic rules on fording water. Flowing rivers, for instance, normally have a more stable base than standing water, and a simple rule of thumb is if you struggle to stand up in the water, the water will wash your car away. Before entering the water, either disconnect the fan-belt to stop the fan turning, or jam the fan (if it has a viscous coupling) with a towel or such-like to prevent the fan turning. This will stop the fan moving forward and damaging the radiator, and prevent it from splashing water up onto the top of any electrical components.
Look at your exit point, remembering that each vehicle will dump about 200 litres of water on this slope when driving out. Think what effect this could have on the last vehicle, and plan accordingly. When crossing flowing water, cross at an angle that is slightly against the flow – this gives you additional time if the water suddenly starts pushing the car, to either reverse or accelerate to the other side.
Once in the water maintain a steady speed, avoiding wheel-spin, as wet tyres are easily cut by any rocks that may be on the river bed. Don’t change gear, as the sudden loss of momentum when depressing the clutch will cause the bow-wave created by the vehicle to splash over the vehicle.
Securing a tow rope to the vehicle before it enters the water will reduce the time that the stuck vehicle will be in the water. Remember, if your vehicle stalls, don’t try to start it.
Instead tow the vehicle out, remove the air filter and check for water. If the filter is wet, remove the spark/glow plugs and turn the engine over on the starter to remove any water.
Check the engine, gearbox and axle oil as soon as possible after deep water crossings and drain the oil if there’s any sign of water (milky colour). Once you are out of the water apply the brakes gently to remove any water and dirt from the brakes. Whatever the terrain, use your common sense, think about what you are heading into and plan accordingly. Again, always take along a decent tow-rope, and a few friends. And enjoy.
This 4×4 Driving Tips are courtesy of Bridgestone