What is the difference between parttime and full time 4wd

Being a typical know-it-all husband, I ran with the question, explaining that the part-time should only be used during certain slippery conditions and disengaged when the condition ends. If you want to leave it on all the time, put it in 'part-time,' because of something to do with the transfer case. The 'full-time' should only be used on a full-time basis when it's slippery outside, again because of something to do with the transfer case.

RAY: Your explanation is exactly right. It's designed to be engaged when you're already stuck, or in a specific situation where you know you might get stuck -- like in snow, sand or mud. It's not designed for normal road use, and must be disengaged before you drive on dry, paved roads.

Plenty of accidents happened due to traction loss, and stability control is recognised as a lifesaver. Now there is an argument that the part-time 4X4 uses less fuel. And that is true. On dirt roads the full-time 4X4 is markedly superior to the part-time 4X4. It has better traction, handling and even braking on those occasions you engine brake. However, those advantages of the full-time 4X4 vehicle can be equalised by selecting 4X4 on your part-timer.

But then you need to remember to select and de-select 4X4 when you drive onto high-traction surfaces like bitumen, or even some high-traction dirt roads.

For example, a big failing is that when you apply the parkbrake only the rear wheels lock, leaving the fronts unlocked and therefore making it hard to secure the vehicle on a hill. There are many claims that such systems improve traction, but the last decade of offroading testing such vehicles has yet to convince me, and no manufacturer has provided proof of their claims either. There is one advantage of a computer-controlled centre diff offroad and that is the turning circle, which is smaller with such vehicles as the computer allows the front and rear axles to turn at different speeds during a turn.

There is one useful, but rarely used feature of a part-time 4X4 system, and that is you can put it in 2WD and spin the rear tyres. I have done this a few times to slew the back end around. But while the Triton system is good, and a significant improvement on the part-time 4x4 systems that are standard ute fare, the Amarok takes things further — in fact, several steps further.

When climbing a steep off-road incline, for example, and the rears have lots of traction and the fronts have little, it can direct as much drive as needed to the rear axle.

This helped make the Amarok a standout on the steep climbs when we tested all eight of the popular utes back-to-back last year. This may be true, but the savings would be insignificant at best, and where does that leave the Land Cruiser and Prado, both of which have full-time 4x4?