Nuccaleena

LOW AND HIGH RANGE OFF-ROAD 4W-DRIVING

The selection of the correct gear and range seems to cause endless debate so I thought I would add my contribution to the confusion this month. Well I am actually hoping to bring it down to a few simple and easily remember rules actually.

When to use four-wheel drive

Four-wheel drive should be used to provide additional traction on difficult terrain. It is a good habit to engage 4WD and lock your front hubs (if fitted), once off the bitumen and travelling on dirt roads. Depending on the track conditions, it is also sound practice to lower your tyre pressures by around 25% and reduce your speed. These habits reduce the risk of a roll-over and/or a puncture.

Depending on type your vehicle will have a range of four-wheel drive selections; it is important to know the general rules for making the correct selection.

H2 is for general highway and town/city driving and on well-formed, graded, compacted dirt roads.

H4 is for use on roads and terrain where wheel slip is expected such as gravel roads, mud, sand, dirt and bush tracks with a high level of traction loss.

L4 (low ratio, four-wheel drive). Use this position when maximum traction and torque

are needed for ascending and descending steep inclines, carrying heavy loads in off-road conditions and when entering mud or sand conditions.

In a non-constant 4WD vehicle it is advisable not to use H4 on roads with a high level of grip or traction as transmission wind-up can and will occur.

Which gear and when?

Without presenting one of our training sessions a couple of simple rules here. Low range is for our wonderful Flinders tracks but in sand you should use high range but the same gear selection. As well this applies to automatic’s which should never be left in drive when off-road. Drive them exactly the same way as a manual transmission.

Going up hill/climbing. Always use a gear higher than First Low. Second or third low are the preferred gears. Why? Well first is too short a gear and you can easily spin wheels, lose traction and then things can get expensive. So a higher gear gives you less chance of wheel spin which is also a very good way of preserving the track you are driving on.

Going down hill/descending. Simply the reverse of climbing. You need as low a gear as you can. Why? Well using the brakes going down hill is not a great idea. Braking can cause a loss of traction and with that comes a loss of control and so it goes. So first gear low range is the best. Let the engine and gears do the work. The slower the better and if it is too slow then you can always gently accelerate a bit. Speed down hill leads to track damage and dented cars and egos so enjoy the view on the descent and be kind to our environment. Remember if you are spinning wheels you are definitely not driving correctly.

Enjoy the drive and the view and leave it in good condition for those that follow.

Of course if you want to know more then join us for one of our training weekends or tours.

Red Earth Expeditions