A loss of traction makes any 4×4 obstacle very difficult to negotiate successfully. And it also has an unfortunate tendency to damage vehicles. Because of this it is very important to try and keep all four wheels on the ground, says Francois Rossouw. If you don’t, you’ll be left with a very expensive repair bill.
Some off-road enthusiasts learn very quickly. They gratefully accept advice and swiftly master the finer points of 4×4 driving. Others, however, are not very receptive to guidance and instead choose to learn through experience. It usually takes them a bit longer to get the hang of things, but they eventually become proficient drivers.
One lesson that everyone quickly learns, though, is that it is vitally important to keep a vehicle’s wheels on the ground. After all, a wheel that is not touching the ground cannot propel, steer or brake a vehicle. Unfortunately, some are forced to learn this (often expensive) lesson the hard way.
On a recent trip into Swaziland we had to cross an axle twister. At the spot where we were forced to scale the hill, a deep ditch crossed the road. The ditch was positioned diagonally, which meant that a front wheel, as well as its opposing rear wheel, entered it at the same time. This caused the front wheel to lift into the air and lose traction. Now, the vehicles with a differential lock – even if it was only at the back – did not have much of a problem. Since the wheels on the same axle were locked together, the one that remained on the ground managed to get the vehicle through. But the 4x4s without a differential lock battled to traverse this obstacle. Their engines revved and their wheels kicked up dust, but they could not make it up the hill without help.
The secret (especially if your vehicle does not have a differential lock) is to choose a route that will keep the axles as parallel as possible, thereby avoiding a cross-axle situation.
Whenever a wheel lifts off the ground, and subsequently loses traction, it is very dangerous to apply a lot of power. If the wheel suddenly reconnects with the ground, a lot of strain is placed on the drivetrain. And this often causes a differential or side shaft to break. Just ask old Land Rover Series Two owners – the models before 1968. They usually carried a spare side shaft wherever they went!
Thankfully, no vehicles were damaged by this axle twister during our recent trip to Swaziland, but this isn’t always the case. I’ve witnessed countless similar scenarios end in sorrow.
A few years ago, while travelling along the West Coast, we came across a very intimidating dune. Needless to say, everyone tried their best to scale this challenging obstacle, but to no avail. A few of them almost made it, but they just didn’t have the necessary momentum.
Eventually, one of the women in our group, Maxi Labuschagne, decided to show the men how it’s done. She grabbed her husband’s keys and powered his Cruiser bakkie up the dune at an alarming speed. She not only made it to the top, but sent the Cruiser flying over the other side. When the vehicle touched down, the grip was simply too much. When the wheels dug into the soft sand, the differential couldn’t handle the sudden strain. The spider gears inside the differential shattered. These shards found their way into and forced the wheels to lock up. Fortunately, the front hubs could be unlocked, so the Cruiser could still continue in 4×2.
But that didn’t really cheer up Maxi and her husband. Maxi was very silent the rest of the trip and her husband was clearly upset by the fact that he couldn’t take part in any of the off-road fun.
The same problem also occurs when traversing mud. Once a vehicle successfully clears a muddy patch, the sudden increase in traction can cause similar results. Luckily, we now have technology that assists us in these situations. Traction control systems, for instance, detect wheel spin and either cuts engine power, or brakes the wheel.
Of course, this means that we have to disengage traction control when traversing dunes. So the driver has complete control. He or she can decide when to apply power and when to brake. Unfortunately, this control often unleashes the urge to show off. And this is too bad, because showing off has resulted in countless breakages. For this reason we don’t invite those who want to show off on our trips. All they do is spoil our fun.