Off-Roader Driving - Hardcover

Über die Autorin bzw. den Autor

During Tom Sheppard's career in the Royal Air Force as a pilot and test pilot he planned, led and trained teams for numerous expeditions and operations - among them the first coast-to-coast crossing of the Sahara through the Mauritanian Empty Quarter for which he received the Royal Geographic Society's Ness Award. He has totalled more than 90,000 overland miles on four and two wheels and has been a Land Rover owner for over 25 years. Apart from navigating jet aircraft his navigation experience has spanned sun compasses, astro navigation, Transit sat-nav and use of GPS and satellite imagery to supplement otherwise uncertain mapping.

Since 1976 and between expeditions, he has worked for British Aerospace and has been an author and consultant on four-wheel drive. On this, the logistics and planning of expeditions and the hugely exciting implications of space technology on mapping, positioning and communications he admits he is unlikely to ever stop learning.

Auszug. © Genehmigter Nachdruck. Alle Rechte vorbehalten.

Section 1.2 Off-roaders - the ingredients As we have a spare right hand page, let's divulge Leonardo da Vinci's perfect 4x4 system (perhaps it wasn't him but it was someone with similarly bright ideas - possibly Leonardo di Caprio?) The next sections will make more sense if you sneak a look at this in advance ...

Section 2.2. What to actually do Priorities. Even if you never use your 4x4 off-road, Section 2.1 is the most important section in the book. Here we have a recap, a check list of what to look for and, in the table, a few examples. The magazines aren't much help; the off-road ones are seldom analytical enough while the others gloss over the 4x4 system - the whole reason for having the vehicle. The brochures aren't much use either, often written by 'creatives' who didn't get the tech brief. Don't buy a 4x4 ... ! There's a market niche for everyone and if you just want the bulk, driving position and space, many of the 'off-roaders' are available as straight 4x2 vehicles! Buy one! Do buy a 4x4 ... ! Hopefully you'll have seen by now there are definite advantages to 4x4 even on-road and, from Section 2.1, that the 4x4 system itself is very important. The more off-road oriented you are the more important are the refinements such as two-speed transfer boxes, diff locks and other means of controlling wheel spin. Check list. Here's what to look for and remember:
Permanent or part-time 4x4?
'Hard' or 'soft' front/rear axle connect.
Lockable centre and/or axle diffs?
Manual or auto diff locks and front/rear interconnect?
Foolproof auto (soft) set-ups usually permit some slip.
Two-speed transfer box?
On the move changes low-to-high range? (Very rare, that.)
Quenching spin or locking one shaft to the other: traction control use of braking system, by selection or progressively?
Auto/manual main gears? (Sec 2.6)
In the table opposite, pick a vehicle you more or less know and follow the ticks down. Use the list above and the numbered headings, right, as your own criteria. Just for you. Between the extremes (below) there are a hundred 4x4s suited to your purpose. If you want the 4x4 aspects of a general family holdall just to guard against occasional winter ice plus you have multiple drivers, some of whom haven't the time to remember about disengaging diff locks on hard surfaces, then go for automatic systems; you'll probably not want 100% power to all wheels so the compromise will not matter. But if a new route in the Sahara or the Brazilian jungle is on your menu then you will need all the help you can get!

Section 3.2 Gentle right foot ... Cadence braking - sheer magic. Best of all, employ 'cadence braking' technique - repeated jabbing of the brake pedal with your foot, quite gently, as fast as you can so that the wheel never gets a chance to lock. Though it takes will-power to take your foot off the brakes to do this when you are trying to slow down, cadence braking is remarkably effective. Cadence braking on-road too. Cadence braking, discovered and taught long before ABS was invented, works well on-road too - probably even more spectacularly. Off-road tyres often lack the on-road grip of tyres designed specifically for tarmac (see Section 8.2) and many is the case of a desert-tyred off-roader in rain on tarmac overseas being saved from certain collision by frantic cadence braking; frantic but controlled ... !

Section 7.1.The call of the wild ... One step at a time equals confidence. Although a gentle progression up the scale of challenge is the natural way to do things, the importance of taking things a step at a time cannot too strongly be emphasised. Going hand in hand with this - importantly and almost inevitably - will be the growth in your confidence. Confidence begets early recognition of, thus avoidance of, and measured response to - problems. Confidence (well-founded confidence, not over-confidence or cockiness) further begets the ability, comfortably, to say 'no' and turn back before getting into trouble. Savour but beware the feeling of amazement and invincibility you may have experienced on your first competent off-road demonstration of your (or your dealer's) off-roader. The feeling of unstoppability is very strong but, as has been emphasised throughout this book, all vehicles have their limitations and in most demonstration you will have been shown what can be done, not what happens when you get it wrong. A significant omission. So, assuming you are just making a start, the answer to the 'day-trip-or-major-expedition' question is clearly 'day-trip' ...

Section 7.5 Logistics, vehicle choice ... The criteria Ingredients. How is an expedition vehicle made up? How is any 4x4 made up? If you are wondering what vehicle to buy next and want to identify criteria a little more incisive than the average brochure-writer's obsession with cup-holders and interior trim look at the list opposite. If the size and scope of your planned expedition or other project demand that you consider what vehicles you need, do likewise. The evolutionary chain. These are criteria that chart a vehicle's growth from a basic two-wheel drive pickup through to an exceptionally capable off-roader. Beware the trap of equating all upmarket vehicles with flabby incompetence. Some are like that; others, even in deluxe trim, are very capable even though their payload may not be as high as a stripped-out pickup.

Section 7.6 Fuels ... High sulphur - what to do? Two things can be done to safeguard your engine by you as vehicle operator: Use an engine oil with a high TBN (see table, page 7.24): 20x sulphur content for indirect-injection engines; 10x sulphur level for direct injection. (So an indirect injection engine in Turkey - 0.70% sulphur - needs oil of at least TBN 14.) Reduce oil change interval - page 7.27.