4x4 Rainforest Challenge, Malaysia
The Rainforest Challenge, held in Malaysia each November, is one of the most memorable 4x4 endurance tests on the planet. Fought out intensely over five nights and six days across nearly 500 miles of the most rugged and unforgiving terrain, the Challenge takes competitors through mud, drenching rain, slippery slopes, deep ruts, gullies, flooded rivers, and landslides that are so demanding and dangerous, it takes hours to travel a kilometer and many more to recover. The difficulty is compounded by the humidity, sand flies, leeches, sleepless nights, unending winching from dusk to dawn, and recovering vehicles submerged deep in tropical mud. But the camaraderie among the competitors was much appreciated, "I have never seen such bonding among the competitors since I came into the Rainforest Challenge four years ago," said Thomas Foo (Tango), the competition manager. "This is definitely a plus for the event."
Loosely based on the old Camel Trophy, the Rainforest Challenge comprises a number of Special Stages, or tasks, featuring extreme winching, mud crossings, slaloming through trees, rockcrawling, and a session of night 'wheeling. In addition, a special Prologue Stage is held, to give the competitors a better idea of what to expect in the jungle.
Last year's event featured competitors hailing from Holland, The United Kingdom, Denmark, Mexico, China, Indonesia, Philippines, Hong Kong (China), Thailand, Korea, and host Malaysia. Immediately after the flag-off, competitors marched towards the Prologue Stage, on Kemasik Beach located on the coast of the South China Sea. It was the first time that the Prologue Stage was held for two days. "It took lots of time and effort to design them to meet the standards that today's competitors demand," said course designer Martin Lewis.
During the race, most teams had a tough time determining and marking the route. Already having experienced torrential rains, overflowing rivers, mud, winching, and washed-away bridges, they spent more time outside the vehicles looking through the undergrowth for signs marking the route than they spent behind the wheel. Expecting that the competitors would have to travel at night and do a lot of navigation in the jungle, a one-night Prologue Stage was held on the beach-with no landmarks, no markers, only running towards the light coming from a burning tire half a mile away. A Korean team went straight into the burning tire and burnt their car into ashes, ignoring the Golden Rule: Finish near the burning tire, and not on top of it!
For all the participants, the following days were tough and had a lot of drama to boot. Clive Paul Raymont from the United Kingdom, in a Suzuki, had a narrow escape when his plasma winch rope got snagged in the winch housing, just as he hung with his Suzuki on the top of a boulder. He was hanging on by only a fiber of the plasma-even the vibration of a heartbeat would have put him into danger. Fortunately he was rescued by event marshals before the rope gave way. During one especially grueling stage, a Herculean effort was required from the four competitors who actually finished, much to the dismay of the other 20 who didn't make it. Another day it took some competitors 18 hours to finish a stage, but five teams had to leave their vehicles in the jungle to be retrieved at a later date.
Another action-packed stage took place in a river with sunken driftwood littering the riverbed to add extra obstacles. All the cars became entangled in it, so the competitors had to winch themselves through the river-a hard job when there are no trees nearby and no solid anchor points. The few moments that the competitors had "nothing to do" was filled in by navigating deep gullies, muddy riverbanks, stony and swollen rivers, steep hillclimbs, bamboo forests, overgrown vegetation, elephant dung every 10 feet, and a constant fight against leeches. An added bonus was the rain-not just a shower, but literally buckets of rain. For some, it was energy-sapping to a breaking point.
There are so many side stories to tell of camaraderie, bravery, continuous driving, recovery, and unending winching for 21 hours at a mud hole. But still, for those who have survived the Rainforest Challenge, it's living out one of life's great 4x4 fantasies.


4x4 (four by four)
vehicle with 4 wheels powered by 4 wheels - 4WD or AWD (four wheel drive or all wheel drive).
4x2 (four by two)
vehicle with 4 wheels powered by 2 wheels - 2WD (two wheel drive).
6x6 (six by six)
vehicle with 6 wheels powered by 6 wheels - 6WD
In 2WD the traction (resistance) of only two wheels is used for forward movement. The other two tires have traction as well, but they are just rolling along. In rear wheel drive vehicles the front tires' traction is used to steer the vehicle. If more torque is applied than there is traction available, the 2 tires will break lose and start spinning. Once the tires are spinning, we say "we lost traction". So, if in need of more power/torque to move more weight or to go faster more traction is needed.
That can be achieved by sending some of the torque to the other two wheels (4WD) and using their traction as well. So, in 2WD torque is equally applied on 2 tires and the traction of those two tires has the burden of supporting the engine's power - each powered tire has deal with 50% of the available torque.
In 4WD torque is directed towards 4 tires. In 4WD the traction at each powered tire has to deal only with 25% of the torque created by engine, transmission, transfer case, and axle. Since each tire in 4WD has to carry a much smaller torque load (25% instead of 50%), it is much much less likely for the tires to break lose. That is why a 4WD can climb much steeper grades than a 2WD.
4WD was invented to use the traction of all 4 tires to either move more weight or drive on surfaces with marginal traction, or both without wheel spin.
Historians seem not certain who invented four wheel drive. According to what I found on the internet, the first 4WD vehicle was designed by Ferdinand Porsche (the founder of Porsche cars) for the Austrian truck manufacturer Jacob Lohner in 1900. The first vehicle in the history of 4WD had electric hub motors on each wheel - the engine powered a generator for power supply.
First mechanical 4WD (transfer case, drive shafts etc.) was built by the Dutch company Jacobus Spyker in 1902. Since the Lohner/Porsche four wheel drive has such an unusual status with its electric hub motors the Spyker should be considered the world's first four wheel drive.
The world's first automaker, Daimler Benz has a solid place in 4WD history as well. Mercedes started building 4WD vehicles 1903 - some of them already with all wheel steering.
The first US four wheel drive vehicle, was built 1911 by the Four Wheel Drive auto company (FWD).
Full time four wheel drive (not to be confused with: part time 4WD ) is a system that powers all four wheels at all times. Each tire gets about 25% of the available torque when the ground is level with a consistant surface. Driver has a choice of a "4-high" (that's your every day setting) and "4-low".
When "4-low" is selected the wheels receive substancially more torque than in "4-high" - at the same time the vehicle moves at substancially slower speeds.
The low setting is an advantage for drivers who need to tow and maneuver a heavy trailer and for drivers who at one point or another may want to negotiate difficult off-road terrain.
All wheel drive (AWD) is a system that powers all four wheels of a vehicle at all times as well. Difference to full time 4WD is that a "4-low" setting is not available. Due to the lack of "low range" AWD vehicles are much less capable in off-road settings than 4WD vehicles.
Part Time 4WD
Main mode is 2 wheel drive for everyday pavement use. Usually only rear wheels are powered (In some cases front wheels are powered instead).
When needed (usually beyond pavement) 4WD can be engaged. 4WD is used part of the time. When 4WD is engaged front wheels are powered as well. There are two different settings for 4WD - "high" and "low". 4WD "high", sometimes called high range, cannot be used on dry pavement with a "part time system. For extreme situations 4WD "low"is available, it cannot be used on dry pavement either. 4WD "low", also called low range, does not provide more traction, however, it provides two to three times more torque at about half or a third of the speeds in high range. For off-road use part time 4WD system is perfect.
Part Time 4WD requires:
· a transfer case
· two drive shafts
· two axle differentials
· two powered axles
· has NO center differential
Full Time 4WD
Also called permanent 4WD and constant 4WD. Main mode is 4WD. 4WD is used full time. No 2WD mode available. All four wheels are powered at all times. Operates well on dry pavement due to a center differential or equivalent device (planetary gears, etc). Part Time 4WD does not have a center differential.
A center differential is essential for on-road use but can be detrimental for off-pavement use. When leaving pavement the center differential needs to be disabled (locked). It either locks automatically or it has to be locked (disabled) manually.
Normal setting for on-road use and light duty off-road use is 4WD "high", also called high range. For more torque 4WD "low", also called low range, is available. Low range provides substantially more torque to the wheels and allows slower speeds than in high range. 4 low does not provide more traction - it only provides more torque.
Full Time 4WD requires:
· a transfer case
· a center differential
· two drive shafts
· two axle differentials
· two powered axles
All Wheel Drive (AWD)
Not to be confused with automatic 4WD. Only mode is 4WD. Full time. No 2WD available. No 4WD "low" available. AWD is almost useless beyond pavement.
Requires:
· transfer case
· center differential
· two drive shafts
· two axle differentials
· two powered axles
"Hidup ini ibarat lautan yang luas terbentang, kadang kala tenang, kadang kala bergelora. Namun sejauh mana pun kita pergi, kita pasti akan kembali... Ibarat ombak yang setia pada pantainya...."