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沙地驾驶的要诀就是保持动力。因为牵引力在这种路况下非常珍贵，所以速度提升难度大。除非不得已，你一定不愿意失去哪怕一点点动力，因为动力失去后可能无法恢复。
轮胎压力
在驶入沙地之前必须要做的事情，就是降低轮胎压力。这样做可以增加你“脚”的尺码，以提供更好的防陷能力，从而显著提高牵引动力。同时，这还可以降低车辆张紧力，并将行进中的磨损和撕扯力降至最小。
最佳的轮胎压力与车型、轮胎型号以及地形有关。下面这个方法可以为你提供一个寻找最佳胎压的起始点，这项工作最好是在驶离柏油路面之前进行。
把装载完毕的停在一处平地上，在距离后轮侧壁1厘米处各放置一块砖。给轮胎放气，直到轮胎侧壁刚好碰到砖块，测量现在的胎压。把测量结果作为沙地驾驶调整胎压时的初始值。当你开始熟悉沙地驾驶的时候，你就可以只根据地形数据来调整轮胎压力了。
如果你没有在进入沙地之前尝试过上述方法，别担心。一个不错的实践经验就是将胎压调整到15psi。
一定要牢记，在降低轮胎压力之前，一定要保证你有一块胎压表，并且有打气泵或类似装置用于恢复胎压。
由于降低了胎压，轮胎变得更脆弱，因而更容易因胎壁摩擦发热或在滚动中脱出轮圈而遭到损坏。胎压越低，损坏风险越高。然而，牵引力方面的收获会很显著，并且可能直接决定你是驱车驶离还是无助地被困。“合适”的胎压取决于你在更佳的牵引力和更高的坏胎风险之间的选择。
在极端糟糕的陷车情况下，轮胎压力最小可以降低到40kpa（6psi）----这是很多轮胎在静止条件下能够保持附着在轮圈上的最低压力要求。在大多数情况下，10psi都应该是调整胎压的最低极限，因为6psi压力下轮胎很容易损坏，比如脱出轮圈或胎壁被刺破。在低胎压情况下应严格控制车速。要降低轮胎损坏风险，重要的是只在沙地上使用很低的胎压，并且在遇到砂石路面或者坚硬些的地面时，及时恢复胎压。如果不能做到这一点，轮胎或轮圈几乎注定被损坏。
沙地驾驶方法
在沙地中开车，你必须努力跟随你前方车辆留下的轮胎印迹，因为这些印迹下的沙子已经被压紧，相比未被走过的沙地要坚硬得多。永远不要在绿色植被上开车，因为这不仅仅会破坏植被，并且会导致水土流失和环境破坏。
在加速或刹车的时候应该避免过快地改变速度。沙地上刹车将会使你的车轮前隆起沙堆，并有可能因此阻碍你前进。快加速只会让你的轮子陷进沙地，并且在事实上减慢你的行进速度。
起步应尽可能平顺并且在换档时保持相当高的转速。沙地驾驶要求足够的引擎动力，以便让你的车“刨”沙前进。在沙地上使用低档前进是明智的做法。因为低档可以成倍增加冗余扭矩，并且在你突然遇到特别松软的小块沙地时提供更多档位。起步前应检查确认轮胎正对前方，以降低对起步动力的要求。
在沙地上停车时，要踩下离合器踏板，让车子滑行，直到完全停止。这样车轮前堆积的沙子最少。在地形允许的情况下，尽量滑行停车，而不是刹驻，并尽可能让车头冲着下坡方向以便于起步。停车时，要避开大多数沙丘及沟渠底部松软的沙地。
沙地转向时，要尽可能拐大弯，以降低陷车危险。在沙地上，你的前轮更像是一只船舵，急转向会造成跟刹车一样的后果。
陡峭的沙丘只能直上直下。如果你以哪怕是非常小的角度驾驶，那么车身重量会传递到下坡一侧的轮胎，如果车身开始打滑，这一侧轮胎会越陷越深并加剧沙丘的坡面角度，进而有可能导致滚翻。
在直线驶下陡峭沙丘时，如果车身后侧开始侧滑，最好是略微加速，试着让车身回到直线行驶状态。这时绝对不要刹车，因为这将导致车身重量传递到前轮，并加剧后段的侧滑。
在驶上沙丘时，如果你没能到达坡顶，要及时切换到倒档笔直退下沙丘，绝对不要滑下沙丘，绝对不要尝试在沙丘上U型转向。
当你从沙滩之旅返回以后，全面冲洗车身以去除沙渍和盐渍非常重要。尤其要注意挡泥板等容易藏沙的地方。同样也要全面冲洗底盘，因为砂砾也会藏在底盘的缝隙或隐蔽处。
沙地脱困
当你陷车的时候，不要试图踏下加速踏板，因为这只会增加脱困的难度。挂入倒档，轻轻地尝试沿着你的车辙后退，因为这会为你提供一条沙子被压紧后的路径。当你后退到足够的距离时，尝试前进并且要小心再次被陷。重复使用这个方法你就有希望每次前进一点，并最终缓慢穿越某块特别柔软的沙地。
如果你不能把车倒出困境，那就下车，进一步降低你的轮胎压力。一个经验原则就是把胎压降低到12psi。在开始倒车之前，清除轮胎后面堆积的沙子。检查车轮下方是否能触到什么（坚硬些的）地方。如果能，就把周围的沙子清除，让车能够倒出来。这个方法你可能要尝试许多次。
必要时，可以继续降低胎压至10psi。此外，绝对不要低估同伴推车对脱困的帮助。前面提到过，极限情况下，轮胎压力可以降低到6psi，但是不到万不得已不要这么做。
如果轮胎压力已经降到最低而你仍然没有脱困，那么你不得不求助于拖车绳，绞盘或举升设备。最简单的办法是拖车绳，但前提是要有能够帮助你的车。如果只有你自己，那只有依靠绞盘或者举升设备了。
沙地驾驶小结
1、降低胎压以获得更好的牵引力车辙坍陷。
2、平顺驾驶，换档时保持高转速。
3、起步时确保轮胎正直。
4、避开沙丘和沟渠底部柔软的沙地。
5、拐弯时弯道越大越好。
6、沙丘只能直上直下。
7、沿着车辙前进，以便能行驶在压紧的地面上。
8、滑行停车，避免刹驻。
9、陷车后不要踩加速踏板。
10、陷车后，尝试沿着你自己的车辙后退。
11、回家后，彻底冲洗车辆。
Sand Driving
The fundamental theme with sand driving is to conserve your momentum. Since traction is at a premium, any increase in speed can be difficult, if not impossible, and you do not want to lose any momentum, as you may not be able to regain it.
Tire pressures
The first thing to do before driving on sand is to lower your tire pressures. This is done to provide better flotation by increasing the size of your “footprint” and thus dramatically improving your traction. It also reduces the amount of strain on your vehicle and minimizes wear and tear on the tracks.
The optimum tire pressure depends on your vehicle, the type of tires fitted and terrain. The following technique provides a good starting point to find the optimum pressure and is best performed before leaving the bitumen.
Part your loaded vehicle on a level surface and place a brick 1 cm away from the sidewall of your rear tire. Deflate that tire until the sidewall just touches the brick and then measure the tire pressure. Use this pressure as your starting point when initially lowering your tire pressure for sand driving. As you become more familiar with sand driving, you can alter this pressure as the terrain dictates.
If you haven’t performed the above technique before you reach the sand, don’t fret. A good rule of the thumb is to use a pressure of 15psi.
Remember though, if you are going to lower your tire pressure, ensure you have a pressure gauge and some means of pumping your tires back up.
As you lower tire pressure, the tire become more vulnerable to damage by stoking the sidewall or rolling the tire off the rim. The lower the pressure, the higher the risk. However the gain in traction can be remarkable and may make the difference between becoming hopelessly bogged or simply driving away. The “correct” tire pressure becomes a decision between better traction versus increased risk of tire damage.
In severe case of bogging, tire pressure can be lowered to a minimum of 40kpa (6psi), as most tire require at lease 6psi to remain seated on the rim while stationary. In almost all situations 10psi should be used as the minimum pressure as 6psi is likely to result in tire damage i.e. tires rolled off rims or punctured sidewalls. Speeds should be severely restricted at these low pressures. To minimize tire damage, it is important that those low pressure are only used on sand and pressures should be increased if limestone or rocky outcrops are encountered, or when the terrain becomes more firm. Failure to do so will also almost certainly result in tire or rim damage.
Sand Driving Techniques
When traveling on sand, you should endeavor to follow in the tire tracks of the vehicle in front as they have already compressed the sand to form a firmer surface than un-traveled ground. Never drive on vegetation as this will destroy it and lead to erosion and environment damage.
You should avoid rapid changes in speed when accelerating or braking. Braking on sand will cause a mound to build up in front of all wheels and possibly prevent your vehicle from taking off. Rapid accelerating simply dig the wheels in and can actually lead to slowing take-off speeds.
Take-off should be performed as smoothly as possible with gear changes done at fairly high revs. Sand driving requires plenty of engine power to get your vehicle “planing” on the sand. It is advisable to use low range as this multiplies the amount of engine torque available and will provide that extra gear if you encountered a particularly soft patch of sand. Check that your tires are pointing straight ahead when taking off to reduce the takeoff effort required.
When stopping on sand, depress the clutch and allow the vehicle to coast to a stop. This will minimize any sand build-up in front of the wheels. If the terrain permits, coast to a stop, rather than braking, with the vehicle pointing downhill as this will aid take-off. Avoid the soft sand at the base of most dunes and gullies when stopping.
When turning, make the turn as wide as possible to reduce the chance of bogging. Your front wheels act more like a rudder in sand and turning too sharp has a similar effect to applying the brakes.
Steep sand dunes can be traversed only straight up or down. If you drive even on a slight angle, the weight transfer is to the downhill side wheels. If the vehicle start to slip, the downhill wheels tend to dig in and make the angle of the dune even worse, leading to a potential rollover.
If you are traveling straight down a steep dune and the back end starts to slip sideways, it is best to accelerate slightly to try and straighten the vehicle. Never use the brake, as this will cause weight transfer to the front wheels and can increase the back end movement.
If traveling up a dune and you do not get to the top, reverse down the dune in gear, NEVER coast down the dune and NEVER attempt a U turn.
When you return home after a beach trip, it is important to hose down your vehicle to remove all traces of sand and salt. Pay special attention to areas like the mudguards where sand is sprayed around and tend to get trapped. Thoroughly hose underneath of your vehicle as well, as there are many nooks and crannies where sand can also get trapped.
Vehicle recovery in sand
As soon as you become bogged, avoid the temptation to simply floor the accelerator as this will just make vehicle recovery more difficult. Put the vehicle in reverse and gently try to back along your tracks as they provide a compacted path. When you have reversed a sufficient distance, try going forward again while being careful not dig yourself in. Hopefully you will travel further each time you repeat this technique and eventually be able to slowly pass through a particularly soft section.
If you cannot reverse out of trouble, get out of the vehicle and let your tires down further. A rule of thumb is to drop them by a further 12psi. Before trying to reverse out, remove the build-up of sand from behind the tires. See if any part of the underside is touching. If it is, clear the sand away to allow the vehicle to reverse out. You may need to try this several times.
If necessary, continue to drop the tire pressure to 10psi. Also, never underestimate the assistance of your passengers giving a push. As mentioned earlier, tires can be lowered to 6psi in extreme cases, but this should be avoid if other means of vehicle recovery are available.
If you are still stuck and your tires are down to the minimum pressure, you will have to resort to a snatch strap, winching or jacking to extricating yourself. The easiest method is usually by snatch strap, but this relies on another vehicle being present. If you are by yourself you will have to resort to winching(if you have one!) or jacking.
Summary-sand driving
Lower tire pressure to get greatly improved traction and reduce track erosion
Drive smoothly with gear changes at high revs
Ensure wheels are pointing straight ahead when taking off
Avoid the soft sand at the base of dunes and gullies
Make turns as wide as possible
ONLY travel straight up or down dunes
Follow in other tire tracks to drive on compressed ground
Avoid braking by coasting to a stop
Do not floor the accelerator if you are bogging down
When bogged, try to reverse on your own tracks
Thoroughly hose your vehicle after a beach trip |