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Off-Road Driving Techniques

By DAVID LOVEJOY

Lesson FOUR - Sand, Snow and the Cross Axle
– sounds like a home mechanics article from 1956!

Sand

Leave it alone and stay well away. The best way to learn to drive in sand is to watch ‘Ice Cold in Alex’, with John Mills and Anthony Quayle. This is also a good way to remind you Americans that WW11 started before ‘Saving Private Ryan’ and ‘Band of Brothers’.

Always walk the sand first…and no ‘buts’.

Always find the firm sand. Do this by looking at your footprint; if you sink there is a good chance that a two or three tonne vehicle will sink further. If you hardly make a mark then that’s the way to go. Soft sand will not support you unless you are travelling at speed – and speed equals mistakes.

Be on the lookout for saltpans and the hard but fragile crust that hides them.

Avoid the edge of the sand close to the water on beaches, as it will not always support vehicle weight.

Stay out of dried watercourses, not only are they full of debris but they are not always as dry as they seem!

Air down (lower the pressure) your tyres to around 15 lbs/sq" (don’t forget to re-inflate when you get back to hard road). This causes a larger ‘footprint’ and thus reduces ground pressure exerted by the tyre.

Do not use aggressive ‘mud’ type tyres; these will simply dig in whenever a slightly softer patch of sand is crossed. You can however fit larger tyres. By larger I don’t mean 44" Supasandshaggers, because unless you follow the route of our American chums your gearing will not stand it. As a prime example if you fit 750x16 Michelin XCL’s to your Series Three instead of its 600x16’s - you will raise your gearing by over 12%. This is as about as much load as you would want to put on any standard drive train. It will also cause your engine to run hotter which in some sandy places is a bad thing!

Keep up momentum – not too fast and not too slow – and try to avoid changing gear unless you can be very delicate with the clutch. Automatics are easier to drive on sand (but come with their own off-road pro’s and con’s). The other, very useful attribute is a massively torquey engine.

When you get stuck, stop and use self-recovery or a friend. I won’t go into the intricacies of Dune bashing or playing in the sand at this moment in time as this series is aimed at the basics first…fun later!

Sand is abrasive and can be very fine in texture, it will get everywhere and it doesn’t like mechanical or moving parts!

Snow

Snow has much in common with sand, it varies in consistency with alarming irregularity - so once again let those feet do their thing. The same rule applies, the further your feet sink, the longer the recovery.

Momentum is once again the secret of forward (or rearward) motion – not to fast not to slow.

Once again airing down can be beneficial but not as low as for sand.

If you lose traction ‘feather’ the throttle gently and slowly swing the steering wheel side to side. If this fails stop and attempt to reverse back the way you came.

I feel that snow has a greater traction coefficient than sand and as such lends itself to more aggressive tyres. This is especially so with heavier vehicles such as Range Rovers or Landcruisers as their weight compacts the snow into the treads of the tyres much more efficiently.

Snow does have the rather nasty habit of hiding wallet-damaging obstacles such as large chunks of the planet! Yet another reason for that pleasant walk before hand.

Snow chains can be of benefit when things get icy or very compacted but are only worth buying if you live in good snow country or you like to search out the white stuff.

You only get snow when it’s cold. You will not notice the onset of hypothermia as much as dying of thirst!

The cross axle


"In the off-road situation nothing stops a vehicles forward motion as often as a cross axle situation". David Lovejoy

How to describe a cross axle? Basically it’s were, due to the unevenness of the terrain, two diagonally opposing wheels have sufficient vehicle weight, thru’ lack of suspension travel, to maintain sufficient cohesion with the ground surface and thus lose traction.

Or

One wheel at the back is spinning and the one at the front on the other side is spinning as well.

Forward motion has ceased…and if you are very unlucky so has reverse motion.

The reason you achieved this new level of the art of Stuck is that your suspension simply does not have enough travel. Interestingly enough most leaf spring lift kits actually reduce suspension travel and at best leave it the same, just further away from the vehicle. Coils are a different world but can be almost as limiting and are definitely not superior. I once compared a series one 86" running on 750x16 SAT’s with standard springs and shackles with a Landrover 90 with a 2" lift (see 1" in real life) and there was virtually no difference in suspension movement.

The easiest way to avoid ‘loss of forward motion’ thru’ a cross axle situation is to pick a route that avoids the extremes of terrain that result in said cross axle. This is easier than it sounds. Simply taking a ‘line’ (not drugs I hasten to add) a couple of feet or even six inches to the left or right can result in a smooth traversing of the route. Approach gullies or ridges at a sharper or shallower angle or turn into or out of undulating obstacles. In won’t take long for you to instinctively take the right ‘line’ – practise makes perfect (ish). And remember to take it slowly and steadily so that if you fail the first time you CAN reverse out and use SLIGHTLY more momentum the next time. Or you can spend hundreds of pounds on Difflocks!

Next month - Recovery and how to look cool….

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