Old-timers will know that you cannot have much fun in a 4×4 until it has suffered some pain.
When it is new, you are in a mental state when every scratch is a major upheaval in your life. But once your vehicle has been damaged and fixed, you will be more prepared for whatever is going to happen next, and things will happen!
The likelihood of expensive damage depends to a large extent on the kind of off-road vehicle you’ve bought. There is a big difference in off-road coping ability between what I see as the four main classes of off-road vehicles:
The best is exemplified by the very expensive workhorse 4x4s that are designed to spend most of their time off the road. These vehicles usually have three diff locks and special fully-floating final drive units. These hubs can be recognised by a (usually) six-bolted plate in the centre of the hub.
This is actually the end of the drive shaft, and if you remove the plate you can pull the shaft out without removing the wheel or even jacking up the vehicle. This layout is universally used on trucks, and is a far stronger construction than the usual passenger car axle. These vehicles should cope with any amount of abuse provided they are serviced regularly.
Luxury 4x4s are often very capable, but they are too complicated and heavy to be taken seriously off-road. Fittings like air suspension and dual-mass clutches seem less capable of taking abuse.
Off-road vehicles based on one-ton bakkies are very popular and they are usually very capable. The fact that they are based on commercial vehicles tends to make them very robust.
Soft-roaders, usually based on front wheel drive family cars, are seldom tough enough or capable enough to be taken seriously. Some of them actually have a note in the owner’s manual to warn drivers that they are not designed to go off-road.
Most modern engines are tough enough to cope with the sort of punishment that they will get when going slowly, sometimes at high revs, on difficult terrain on a hot day. This kind of motoring puts extra emphasis on cooling provided mostly by the radiator fan, and in extreme conditions an engine may overheat.
Engines being operated in dusty conditions need fresh, clean oil and petrol filters more often. Air filters should get special attention, especially if you have negotiated some streams. Both sand and water can cause an air filter to close up, resulting in a reduced air supply to the engine.
In a petrol engine, this may cause an over-rich air/fuel mixture that will show up in excessive fuel consumption and a loss of performance.
In a diesel engine, dirty filters will cause overheating because the engine always needs an oversupply of fresh air. If this supply is reduced, black smoke and a wrecked turbo are bound to follow.
Oddly enough, manual transmission vehicles tend to suffer more than automatics because most drivers slip the clutch too much when starting off or negotiating a slow-speed section. This causes excessive heat and wear.
If you often go into water, both the gearbox and the final drive unit will have to be fitted with proper breathers that won’t allow water into these casings. Some of the top 4x4s are equipped with such breathers.
Off-road driving often plays havoc with wheel alignment, but it’s not practical to have your alignment checked after every off-road adventure. The best you can do is inspect your tyres frequently, and get an expert’s opinion if you see any unusual wear patterns.
The tyres must be suited to whatever kind of motoring you do most. Off-road tyres are available in off-road/on-road driving percentages that vary from 40/60, 50/50, 60/40 and 70/30 to 80/20. This wide range of choices makes it easy to choose the best tyres for your kind of motoring, but it also means that you will often come across sections where your choice of tyre will be unsuitable.
The suspension will take a hammering, and it will be worth your while to examine the suspension and shock absorbers from time to time for any signs of damage. Experience has shown that beam axles suspended on coils or leaf springs tend to be more robust than independent suspension. In the latter case, some brands use coil springs while others employ torsion bars. There’s very little to choose between the two layouts.
The underbody should also be examined regularly for signs of damage to brackets, pipes, mountings, steering gear and anti-roll bars. On a dedicated 4×4, some parts will be protected by suitable shields, but on the less expensive vehicles this will not be the case. Make a particular note of the catalytic converter’s position and shield (where fitted) because it runs hot enough to set fire to dry grass and leaves. Look in your owner’s manual to see if there is a warning about where you should not park your vehicle. – Jake Venter