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One of the most important lessons to learn about off-road
driving is that the aim should be to get to your destination
without damage to the vehicle, the land, or yourself. Don't
think of it as a speed trial - steady, careful progress is
always best.
Engage 4WD as soon as you leave the road. A Mitsubishi in
2WD will easily cope with gentle off-road terrain, but in
4WD there's less chance of being caught out by surfaces that
are much more slippery than they look. Wet grass, for instance,
can be treacherously slidey. And in 4WD there will be less
wheelspin - and so less chance of damage to the ground.
Before you attempt to cross any serious terrain, get out
and take a close look at the land - you'll learn a lot about
it. How soft is the mud, how steep are the hills, how deep
is the water, how many rocks are there? Knowing all this will
be a big help when planning and driving the route.
ENGAGING LOW RATIO
When you encounter mud, slopes, rocks and generally extreme
conditions, that's the time to engage low ratio. You're unlikely
to get through without it.
Soft deep mud, for example, sucks the vehicle down and places
such a drag on the engine that there's a real chance you'll
stall if still in high ratio. But in low, engine revs will
be higher, therefore giving the vehicle a much better chance
of powering through the quagmire.
The benefit of low ratio when negotiating rocks or extremely
uneven surfaces is that it allows the vehicle to creep forward
without the need to slip the clutch.
REAR DIFFERENTIAL LOCK
Various Mitsubishi 4x4s have a lockable rear differential,
and this can help in extreme conditions when not even 4WD
low ratio is enough.
Because the diff lock gives side-to-side locking on the rear
axle, it's particularly useful when one of the rear wheels
loses traction, say when crossing a ditch at a diagonal angle.
Normally the drive would disappear out of the spinning wheel,
but with the lock on you can keep moving provided one rear
wheel has traction.
DESCENDING STEEP SLOPES
For those with no 4WD experience, the technique for steep
hill descent can be daunting, but with care it's really quite
easy.
Line the vehicle up with the path of descent, ensure first
gear low ratio is engaged, and drive the vehicle very slowly
over the brow of the hill. Once the descent begins, on all
but the steepest slopes you need to do nothing more than steer,
as the low gearing combined with engine braking should lower
you slowly down the slope.
Should you find yourself needing to use the brakes, extreme
caution is necessary to ensure you don't brake so hard as
to stall the engine or send the vehicle into a slide. And
should you find yourself on a slope so slippery that the vehicle
is travelling faster than the wheels are rotating, you will
need to accelerate to regain steering control.
But braking and accelerating on hills are two difficult techniques
to master, and two good reasons to stick to less ambitious
slopes until you've gained the necessary skills.
HILL CLIMBING
The successful ascent of a steep incline involves traction,
momentum, and a steady throttle foot. And as with the downhill
descent, keep the vehicle as straight as possible.
Low ratio is a must and second gear is usually the best choice
unless the hill is really steep (if you're driving an automatic
4x4, keep the selector in Low). The gear you start off in
is the one you'll stay in.
To maximise momentum, approach the slope at a brisk pace,
but not so fast as to risk the front bumper digging into the
ground at the point where the incline begins.
REVERSING BACK DOWN
As soon as it becomes clear you aren't going to make it to
the top of the hill, you need to get into a position where
you can easily and safely get back down to the bottom so that
you can try again.
Lift off the accelerator and apply the footbrake and clutch,
which should hold the vehicle steady. Then select reverse.
Release the brake and clutch together, and allow the vehicle
to descend, using engine braking alone (you will of course
still be in low ratio).
Keep both hands on the wheel and make sure you're backing
down square on to the hill, because if you stray off line
the vehicle could end up sideways across the course, which
could in extreme circumstances result in it rolling over.
The procedure for automatic 4x4s is similar. At the point
of ascent 'failure', brake, let the revs die, select 'R' and
reverse down.
If in a manual vehicle if you stall the engine, don't panic.
Brake, select reverse, and with the clutch engaged gently
lift you foot off the brake; at this point gravity might take
over, the backward movement bump-starting the engine. If not,
with no feet on any pedals briefly turn the starter and that
should get you moving.
OTHER USEFUL TIPS
STEERING
In really soft or muddy conditions the vehicle has virtually
no steering effect, thus it can be difficult to know which
way the wheels are pointing. So count the number of turns
of the wheel you make in each direction.
STEERING WHEEL
Don't rest your fingers through the steering wheel spokes,
because sudden jolts fed back to the steering can wrench the
wheel round and cause injury.
KEEP THINGS SECURE IN THE CABIN
Tie big objects down, because once the vehicle assumes extreme
angles these could fly around. Stow small items away, as in
a steep descent they could get into the footwells and under
the pedals.
BRAKING
Remember you have much reduced braking on loose, gravel surfaces.
Gentle pressure on the pedal gives more effective braking
on this type of surface.
TEST THE BRAKES
Always test the brakes after passing through water - pressing
the pedal gently for a few seconds while moving dries them
out and restores efficiency.
TYRES
In really bad conditions partially deflating tyres can give
you more grip - but make sure you have the means to re inflate
them afterwards.
READ THE HANDBOOK
Even if you know when and when not to engage 4WD and low ratio,
the relevant section in the handbook may well give you extra
useful information.
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