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If you have not used a 4WD system on a older 4WD with manual hubs, please read here to prevent potentional damage to your hilux.

NEVER USE 4WD ON ANY ROAD SURFACE WITH GOOD GRIP!

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Here is how you use your "Part Time" 4WD Hilux most efficiently:

First a hilux is called part time 4WD as it is not designed to be used in 4WD all the time. Unlike a 4WD sports car, they are designed totaly diffrent.

• Drive in 2WD most of the time (that's where the name "part time" is coming from - you use 4WD only part of the time)
• Only use 4WD when you encounter snow, ice, mud, or rain on a road with very very little grip. Don't forget to lock your hubs if they are manual*.
• Go back to 2WD as soon as you encounter a surface with good traction.
• If you encounter turns while in 4WD just know that the steering will not be as crisp as in 2WD (understeer will occur & the turn might be wider than normal).
Please read Axle/Transmission Windup below for the problems caused by running 4WD on the road.

Manual Locking Hubs - Why?

• With the hubs in the "unlocked" postion your front wheels just spin totally independent from everything (its as simple as that).
• With the hubs in the "unlocked" position if you select 4WD the front prop and axle will turn but not turn the wheels as they are "unlocked" from the drive shafts.
• With the hubs in a "locked position when you drive down the road the front wheels will turn but they will also turn the drive shafts, front prop and the whole front drivetrain. This just causes unecassary wear and stress for no reason. (This will not damadge anything but parts will be worn).
• With the hubs in a "locked" position and you select 4WD the 4WD system will correctly power all 4 wheels.

If you live in an area were during winter for example you have lots of snow some people will leave the hubs locked for this time so when there is snow it is just a case of selecting 4WD on the stick.

The owners manual also suggests that once a month you should drive about 10 or 20 miles with the front hubs locked as some parts are only lubricated correctly this way.

Axle/Transmission Windup

When a 4WD is travelling in a straight line all four wheels rotate at the same speed, but during cornering each wheel travels at a different speed due to the radius of the turn. All vehicles have a differential on the front and rear axles to allow the wheels on the same axle to rotate at a different speed.

Constant 4WD’s have a "central differential" fitted to allow for different speeds between front and back wheels, but most part-time four wheel drives do not.
When a part-time 4WD (without a centre differential) is in 4WD an attempts to corner on bitumen, all wheels need to rotate at different speeds, but without a centre differential they cannot.

This creates the phenomena called "axle windup" or "transmission windup". High strain is placed on the drive shafts and transmission, eventually causing one of two things to happen. Either one of the wheels slips or spins to overcome the stress or the drive-shaft/transmission breaks. This is why part time 4WD’s should never select 4WD on tarmac or a surface with good grip. Constant 4WD’s have a central differential within the transmission to overcome this problem.

However once in the dirt a constant four wheel drive can be bogged with only one wheel spinning. This is why they have a central differential lock that stops the action of the centre diff and makes it like a part-time four wheel drive in 4WD mode. The centre diff lock should never be used on tarmac or non-slip surfaces for the reasons mentioned above.

In reality, a 4WD is only a two wheel drive with one front and one back wheel driving when traction is lost. One wheel on each axle spins while the other receives no drive at all due to the action of the differential. The exception to this is where a limited slip or locking differential is fitted. A limited slip diff allows a limited amount of drive to be applied to the stationary wheel before the other wheel on the same axle spins. A locking diff allows no slip at all and both wheels on the same axle turn at the same speed, regardless of the amount of traction.

Undoing Axle Windup

To undo axle windup assuming you havent damadged the axle or transmission. You can either reverse slowly for about 5 meters, or another method is to slowly reverse up a kerb at an angle where one wheel will slightly lift of the ground.

Also see these links.

What is low and high range and when do I use them?

Basic guide to 4WD driving.