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I found a very good write up on the topic of Offroad driving techniques and thought I'd share with the rest of the community.
Source:
A Guide to Off-Road Driving
1) Read your owners manual thoroughly before going off-road, or on road for that matter. Learn your vehicle.
2) Never go out alone. A short venture could be costly. One thing we try to stress during our Off-Road Training classes is that you should never venture
off the highway alone, even more so in the cars of today. With all that electrical fun and games bolts on here and there, you’d have a very slim chance of
driving out should a major problem occur. Remember the western bound pioneers? Do you have any idea as to how long it took them to cover ten miles?
How about the hardships involved? Lack of water? Lack of shelter? Poor clothing? Have you thought of these things? NO?
Just think, what if... You are ten miles off the main paved road, your 4WD quits, possibly you have an accident, now what? Your cel-phone doesn’t work,
no one in sight, do you sit tight? Walk out? Something to consider, isn’t it? Okay, so you walk, do you have the right shoes? Clothing for when it gets
cold at night? Water? Well? Lots of questions, but few answers. One can’t foresee everything that could go wrong, and shouldn’t try either.
Being prepared yourself and having your vehicle prepared and maintained to a reasonable degree will help counter some problems. Taking along another car
is a smart thing to do, chances are both cars won’t quit while out. The second car could surely tow out the first, or go for help if necessary.
3) Always make sure your vehicle is prepared before departing.
4) Adopt a relaxed and upright driving position with a loose grip on the steering wheel, taking note to keep your thumbs out of the center section of the
wheel, thus avoiding broken thumbs from steering wheel kick-back. This is a common problem on vehicles not equipped with power assisted steering.
5) Contact between your right foot and the gearbox tunnel will help increase throttle control. The use of a "dead-pedal" on the left is also helpful.
DO NOT use the clutch pedal as a "dead -pedal". Once the clutch is engaged (out), keep your foot clear.
6) Know your minimum ground clearance. On vehicles equipped with liveot; axles (fixed), the minimum ground clearance is the lowest point of the axle housing, normally the differential. This minimum clearance always remains the same as the axle goes up/down with the wheels. To obtain your minimum clearance, measure from the differential housing (its lowest point) to the ground, there it is, your minimum ground clearance. The minimum won’t change, though maximum can when a wheel climbs up.
Attachment 579491
The Live axle always maintains its minimum ground clearance (arrows left).
6A) On vehicles fitted with independent suspension however, the front wheels are attached to the A-arms which go up/down independently from each other, at the same time the center portion of the chassis/suspension goes up/down as well, though the exact opposite of the wheels. Type of terrain, as well as braking can effect your ground clearance dramatically; when the front wheels are bottomed on their suspension points (up in the fenders as far as they can go), your chassis and front suspension pivot points are now very vulnerable to damage as they come closer to the obstacle. It is a proven fact, that for heavy duty off-road work vehicles fitted with live axles are preferred.
Attachment 579492 Attachment 579493
As you can see from above, the ground clearance varies as the suspension moves up/down. Left: In its unloaded position you could have 8 (example), while Right: In its bottomed position it could reduce to half. Always be aware of vehicle ground clearance and obstacles.
7) Suspension & Wheel Travel. Since the time man first developed wheeled vehicles his thought must have been on smoothing the ride. Leaf springs have been
around since what must be the beginning of time. Horse drawn wagons, buggies and the famed stage coaches had leaf springs. The leaf spring has two advantages
over any other form of suspension, in that a) it’s cheap to produce, and b) they will carry heavy loads. A number of today’s 4wds are still built with leaf
springs (on a HD pickup its understandable), while others have gone the Coil spring route. Coil springs do allow heavy carrying capacities to an extent
while offering a smoother ride and better wheel travel/articulation (movement up/down & angle of axle). Other manufactures have sought to create car like
rides on their 4WD vehicles by fitting independent front suspension, either torsion bar or coil sprung, though neither of which is in its element when
off-road. The best set up? Coil sprung/Live axles; this set up offers smooth ride with extreme rates of wheel travel (wheel movement up/down) and is still
cost effective to build. Independent front suspension, as described in #6A, is expensive, car like, and offers little to the off-roader, as it can be
damaged easier than a live axle, has more pieces to maintain/damage, and can not offer the wheel travel and stability when off-road.
8) Know your Approach angle, Break-over and Departure angle (Below). Knowing these figures (i.e.: Clearance), you’ll be able to negotiate obstacles much easier without damage to your vehicle.
Attachment 579494
Interested in learning what these figures are on your vehicle? Try a long broom stick. Placing it under the edge of the tire, then lifting up until it makes contact with the body, you now have some idea of your angles. When off-road, drive up to your obstacle lowly, then stop get out and look to check clearances upon approach. When clearing the obstacle, be careful to walk the rear wheels off, remembering always that most 4WD vehicles have some sort of overhang beyond the rear axle (when walking your 4x4, the use of brakes, a spotter and your own sight
will enable you to creep the rear wheels off the obstacle). Damage will result if care is not taken. As far as break-over is concerned, also know as
high-centered, this too will take a keen eye, the assistance of a spotter, and practice.
9) Know your vehicles height and width. Think about parking garages and parking spaces, will your 4WD clear the obstructions within the structure?
Now apply the same to overhanging trees, narrow washes and rocks. Easy really.
10) Check the area(s) in which you plan to travel off-road. Ask locals about conditions. Purchase and review local maps. And... When in doubt, get out and take a brief walk to review the terrain ahead. This walk could save hours of digging and/or winching, or the anguish of having your new 4WD damaged.
11) Be aware of changing weather conditions, the last thing you want is to get caught on the desert floor. When in doubt head for high ground (when heavy rains come in), and get out of the washes or off the desert floors. Beware of fast running water... if you can’t swim it, don’t drive into it.
Many vehicles have been lost in rough weather and water. Beware!
12) Know your Four-wheel-drive system. Unlike days gone by, the systems of today vary in their modes of operations and capabilities. Review your owners manual or talk with an expert concerning your vehicle make. Don’t assume anything.
13) Engage Low-Range before you need it. Choose the correct gear for the situation, see #12. Note: On vehicles fitted with a manual center Diff-Lock,
this should be disengaged once traction has been regained. However, Low-Range should be kept engaged until clear of the hazardous area(s). FYI: This center
differential-lock is just that, a lock, locking the front & rear drive outputs of the transfercase together. When unlocked (disengaged) it will prevent
"axle windup" with in the drivetrain. Vehicles fitted with a standard High-Low/2wd-4wd system have no center-differential, and when engaged in 4WD for long periods they will induce axle windup. You may notice that in tight turns while in 4WD that the front wheels will seem to hop and buck, this is the windup trying to escape from the system. Don’t be alarmed.
14) Before entering a difficult section, make your choice of gear selection. Remember that you should ALWAYS use lst gear (First, Low-Range) on down-hills for maximum engine braking effect, and keep the use of brakes to an absolute minimum, the use of which could cause sliding and loss of control. To correct a sliding vehicle, turn into the slide and apply some throttle, you will now have to straighten the steering wheel and let off the throttle. Gear selection for up-hill use depends on the make of vehicle, though 2nd or 3rd would be a good place to start. Choosing too high a gear can lug or stall an engine, keep you eye on the tach. Using steady rev’s of 1800-2200 rpm is a good starting point.
15) If conditions are soft (marshy ground, sand, etc.) it may be advisable to lower tire pressures. This helps improve traction, and will reduce sinking.
Tires will have to be re-inflated for road use.