What is 4WD System?

The main component that differentiate the 2WD (normal vehicles) and 4WD is on their transmission system or an automotive drive system in which mechanical power is transmitted from the drive shaft to all four wheels.

Normal vehicles only powered by main gear transmission box as compared with 4WD vehicle is also attached additional gear box or transfer case/gear which usually located behind the gear transmission box.

Transfer case main function is as a housing for drive shaft/propeller shaft to move the wheel forward and backward. Transfer case box possess 2 additional set ratio gear that are high (4 High/4H) and low (4 Low/4L).

When you choose a low gear ratio that mean you are doubling the torque to the wheel. Low torque circle with the mechanical transmission system enable all four wheel advantage to climb or to carry heavy load. Please remember that with 4 Low gear ratio does not give you wheel grasp but only to supply more torque for your wheel.

There are two type of 4 wheel system that is full time 4WD and part time 4WD.

In my case,my Mitsubishi Pajero is classified as a part time 4WD and this type of 4WD become more popular in Malaysia.

When to use 4H:

• for traction when the area isn't steep
• when stuck in sand
• extremely slippery conditions
• snow
• ice
• rocky, gravel roads
• gullies
• extremely muddy areas
• ridges

Low Range 4WD

4L is for creeping along at slow speeds. It reduces the strain on your vehicle, just remember to stay below 25mph in low range. While it does not provide more traction, it does provide 2-3 times more torque at about 1/2 or 1/3 of the speeds in high range. Low range gear ratios are approximately half that of high range.

When to use 4L:

• on wet, slippery surfaces
• passing through sandy areas
• on rough trails
• through shallow water
• rock-climbing
• climbing steep hills
• through mud
• descending steep hills

Additional Tips:

Don't change gears in the middle of a water crossing, going up or down hills, or in sand dunes.

Be prepared: Engage low-range 4WD before you need it.

Don't operate 4WD on hard dry surfaces.

When in doubt, use a lower gear!