YOUR OFFROADING POCKET GUIDE
Welcome to 4x4 Gulf Offroad! We’re excited to welcome you into 4x4 Gulf, a club of offroad enthusiasts. It’s going to be fun, exciting, worth every adrenalin rush and most importantly, a safe environment for you to learn and understand the basics of offroading.
If off-roading is what you live and breathe over the weekends and isn’t something new to you – welcome! We hope you enjoy your rides with 4x4 Gulf.
This article will help provide you with an overview of what you can expect and what you need while hitting the dunes.
BASIC OFF-ROADING EQUIPMENT
- Radio/Walkie Talkie
- Off-roading Flag
- Tire Deflator
- Tire Pressure Gauge
- Air Compressor
- First Aid Kit
- Recovery Kit
- Kinetic Rope
- Soft Shackles
You might find that it gets extremely hot in the desert, especially during Summer months. Make sure that you always carry enough water and some light snacks such as nuts with you.
But most importantly, a big smile and a positive spirit J
Off-roading is an exciting sport and we’re sure you’d love to bring your friends and family along. We recommend that on regular drive days, you bring 1 additional passenger along. More people will add more weight to your car, making it tougher for your car to perform to its maximum capability.
We do also organize more relaxed events and days especially for families.
GETTING FAMILIAR WITH YOUR CAR
Reducing tyre pressures is essential once you leave the road and enter the desert. Experience and knowledge of your tyre and vehicle capabilities will tell you what pressures to use for different circumstances but as a guide the following information is relevant. Recommended Pressures for Dual Purpose Tyres:
Large 4WD vehicles - 16 psi
Small 4WD vehicles - 15 psi
Tyre pressures should be taken when tyres are cold. Pressures will build up from use and in hot weather by anything from 5 to 7 psi. So if you get stuck in soft sand your first check should be the tyre pressures. If they have built up, reduce them and that may be enough for a self-recovery.
Note, that these PSI’s are only indications of your tyre pressure range. Your marshall on the drive will be able to advise you the right tyre pressure based on your tyres and car. As you learn more about your car, you will be able to guage tyre pressure based on your performance on sand.
Most desert driving over level ground and low dunes should be in High Range.
Low Range should only be used in specific situations when negotiating an obstacle or for self-recovery exercises. The constant use of Low range causes vehicles to over-heat and consume excessive fuel. When in Low Range the engine is reviving faster, at any given speed, when compared to being in High Range.
For self-recovery from soft sand the first option is Low 2nd with a very light throttle pedal pressure. Excessive engine power only spins the wheels and you will go down - not forward or back! Low Range has very useful characteristics especially for controlling your vehicle on steep descents by offering excellent engine braking. This means that when you remove your foot from the accelerator, the vehicle is slowed by the engine and you do not have to use your brakes.
PREPARING YOUR VEHICLE
Most 4WD vehicles are regularly used by their owners as everyday transport and off-road excursions are weekend trips, once or twice a month. However, going off-road will put additional strain on the vehicle and small problems that would not normally arise with normal use may cause serious problems if you are out in the middle of nowhere.
Every off-road trip should be approached seriously and systematic routine checks must be made before starting.
The items to check are as follows:
1. Condition of the tyres: Check for cuts, bulges or other signs of damage. Also check that the spare tyre (always take one with you) is inflated and serviceable. If the spare is mounted underneath the vehicle or on the rear door, make sure it is firmly secured with the necessary wheel nuts or other fittings.
2. Water level in the cooling system: Most modern vehicles have a water catch tank fitted and it is this that is topped up rather than the radiator itself.
3. Engine oil level: If your vehicle has automatic transmission, check the level of the auto box.
4. Hydraulic clutch and brake reservoirs should also be checked.
5. Battery check: If you are adventurous when going off-road, you may have placed your vehicle at steep angles, front, rear or sideways and there is a possibility that some battery acid has spilled onto the top of the battery. It is advisable to wipe it clean as acid corrodes surrounding parts including the clamps.
6.Fuel tanks: Fill up before you leave and start with a full tank. If you find yourself worrying about how much fuel you have left, you may not be concentrating properly when tackling those tricky sections.
7. Interior Stowage: Make sure all equipment including tool-boxes, camping gear etc is firmly secured in the back of the vehicle and not liable to start flying around when going over rough ground or up or down steep slopes.
GOOD DRIVING HABITS
Whether this is your first or hundredth time on the dunes, everyone can benefit from brushing up on their technique to get the most out of their drive. Here are few ideas for improving your desert driving techniques.
Line Of Least Resistance
TRY to take the line of least resistance when tackling an obstacle. Whilst you should always tackle smooth slopes in a straight line there are some climbs where the ascent can be better made by a meandering route which follows step by step ascent thus reducing the overall angle of climb.
Keep Your Distance
WHEN TRAVELLING in convoys some drivers have a bad tendency to drive too close to the vehicle in front of them. This causes serious problems if the leading vehicle runs into difficulty or has to stop suddenly or wishes to reverse back along his tracks as the follower has little time or space to take evading action and he himself becomes stuck
A reasonable distance to maintain is about five vehicle lengths when driving over dunes and rough ground. This will give a clear view and sufficient reaction time if problems occur. When driving in convoy on tracks at faster speeds, use 100 metres as a minimum distance between vehicles.
Don't Stop Where You Can't Start
THIS APPLIES mainly when ascending slopes and failure to observe this rule is the main cause of inexperienced drivers getting stuck. Never stop on the top of a dune - go over the top and stop on the downward slope so that you can start off again. Never stop astride the ridge on top of a dune. Always stop on a downhill slope whenever possible.
Ascending the steep slopes of a dune or a ridge requires one basic ingredient - MOMENTUM. There is no substitute for momentum. If you start to lose forward momentum your vehicle may falter and then dig in.
Climbing steep sand slopes is a different process to climbing earth or stony slopes. When the ground is hard and firm the technique to use is one of slow and steady progress picking your way carefully up the slope and using the path that offers the best grip you can find. Sand surfaces do not offer the same degree of traction as a hard surface so you need to build up a head of steam on the approach to the slope to allow the momentum of the vehicle to assist the driving force of the wheels once you are on the slope.
You must learn to judge just how much momentum is needed and how much speed you need to build up on the approach run to a slope. It can be dangerous to use excessive speed and risk losing control of the vehicle if it hits an unseen bump in the ground. The choice of gear is also important on your approach run. Select a gear that will enable you to build up momentum and which can be used for the ascent without having to change once on the slope.
Driving down a steep dune several hundred feet high is a daunting prospect for the first-timer. Apart from the courage required you also need to know what to do and what not to do. Gravity is a powerful force and a 2 ton vehicle on a 35 degree slope needs to be controlled by the driver.
After you have made your visual check of the slope and decided which path to take, remember the basic rules for descending sand dunes.
- Always drive straight down a slope - not at an angle
- Do not use your brakes on a steep slope - the act of braking transfers the weight of the vehicle onto the front wheels which will dig into the sand. The rear of the vehicle becomes lighter and will have a tendency to slide sideways and the risk of overturning is very real.
- Never try to coast down a slope in neutral or with the clutch pedal depressed. The soft sand will not allow the vehicle to roll forward and it may start to slide sideways and roll over.
- Always be in gear and DRIVE down a slope with the engine pulling the vehicle. The choice of gear is very important - if you are in High Range your speed may become too fast and you will be tempted to use the brakes - with disastrous results. Better to select Low 2nd or 3rd gear for the descent. If your speed is becoming too fast all you have to do is lift off the accelerator pedal and engine braking comes into effect.
Everyone gets stuck from time to time and here are a few tips and ideas to reduce the agony of self-recovery. Every vehicle needs to carry certain equipment on board to assist in the recovery process.
When traversing dune slopes, the vehicle has a tendency to slip sideways down to the bottom of the slope and you may have to counter this by steering uphill slightly and applying more power to the wheels. If you seriously think the vehicle is about to roll over, do not steer uphill but turn the front wheels downhill to regain control..
Watch out for any undulations in the surface of the slope especially if driving near to the maximum angle of lean. A sudden bump or depression could throw the vehicle off balance and over the limit.
Crossing Ditches and Gullies
The most difficult ditches and gullies to deal with are those at the bottom of a dune followed immediately by a short bank.
In cross-section the ground would resemble the shape of a modern hockey stick. The danger is getting stuck with one or more front wheels firmly bedded in the bank with a rear wheel off the ground. Another danger is getting trapped and self-recovery work would be required so a tow from a colleague is the best option.
One trick to avoid getting trapped in a gully is to swing the vehicle sideways as you reach the bottom of the slope. This may cause the vehicle to lean over as the back slides sideways but at least all wheels will remain in contact with the ground. You can then drive with two wheels on the slope and two in the ditch until you come to a place where you can drive out of the gully.
As a general rule you should cross holes, ditches and gullies in a diagonal direction at an angle of 45 degrees. This will enable the vehicle to maintain at least three of the four wheels in contact with the ground at any one time and maintain traction. If you drop both front wheels into a ditch together you may finish up with the front of the vehicle firmly wedged against the far bank and damage the bodywork
GOOD TO KNOW
READING THE SAND
Learn to distinguish between different types of surfaces in the desert. Each aspect of the ground has a message for the skilled driver.
Stretches of sand with a rippled surface are likely to offer a firmer grip than smooth sand. Pale yellow sand is generally of a coarser nature than the fine grains of the golden red sand and will be easier to drive on - to a degree.
In the bottom of a blowhole or a hollow between large dunes there will be loose sand that has been blown off the top of adjacent peaks. These hollows are potential danger spots as the sand is soft and powdery and offers little traction. If you find yourself in a blowhole keep moving, don't stop, until your vehicle is on the slope of the hollow.
TYPES OF DUNES
Dunes come in three basic types - the crescent shaped called Barchan, the ridge type called Seif and the mini-mountain type called Draa.
The Barchan dune's crescent shape is created by the prevailing winds which form a shallow slope on the side facing the wind. The reverse, or lee, side is much steeper and can be a 30 to 45 degree slope with a concave profile.
Running along the top of these dunes there is usually a narrow peak which slightly overhangs the lee slope. In practice these peaks will crumble away with the weight of your vehicle providing you are brave and do not stop with your wheels astride the peak. Stopping in this position is one of the most common causes of getting stuck.
If you are unsure of the way ahead, stop the vehicle in a place where you can start off again - NOT on the slope near the top of the dune. Walk ahead to see the lie of the land before going over the top. If you stop on the approach to the peak or astride the peak you may need to do some serious recovery work.
Seif dunes owe their shape to the prevailing winds not always blowing from the same direction. The dunes assume a profile similar to that of a wavy edged sword with a central ridge down its spine. It is not unusual to find Barchan and Seif dunes occurring in isolated pockets in otherwise generally hard and flat sandy regions.
Draa A large continuous area of soft sand is called an Erg and it is in these areas that the high Draa dunes are found.