Its simple. One thing, and one thing alone will ensure you make it up that hill, through that puddle, bog hole or swamp. It’s the one thing that when taken from your vehicle you become stuck. Its called MOMENTUM. Don’t be fooled though, there’s a definite clear line between enough momentum and too much momentum. Go to fast and your out of control, too slow and your going to get stuck.
Traction. It’s the key to momentum. Going “just fast enough” with your wheels spinning is as good as being bogged. I’ve seen so many younger four-wheel drivers, start their ascent up a hill, going flat-out, wheels spinning, and get no further that the guy before him going to slow. When you spin your wheels, you no longer have control of where your going, and all to often end up with the vehicle on its roof or side.
Ideally, you should be travelling at the speed your going to ascend the hill at the start of it, and in the gear (if your driving a manual) that you’ll use the whole climb. Changing gears on an ascent will cause loss of traction or a stall. This can end up with disastrous consequences.
Your line. Walk the hill first, check for anything that can cause you to lose momentum. The height of your vehicle, the clearance of your undercarriage (Differentials, fuel tank, tow bar) are important things to take into consideration. Most people have no idea. Having enough momentum isn’t going to make a difference if you bottom out half way up the hill or halfway through the puddle. The last time I bottomed out, it was in a deep puddle. The tyres sunk half way through causing my vehicles belly pan to touch, I came to a grinding halt, and the water started to come in, filling my foot wells with the most horrible smelling liquid. No amount of momentum would have helped. Not without causing damage.
Sand driving. Here’s where you need a lot of momentum. Stop in soft sand and you’ll never get going again without sinking. Going up hills in sand is simple. Go as fast as you can safely. One thing you must know though, your steering will be sluggish, and the tighter the turn, the more likely you are to get stuck. If you do stop, use MaxTrax or something similar to get going again. The key is to create momentum again, and don’t stop. Spinning tyres in sand will dig a hole faster than a shovel. Keep your tyre pressures to a minimum to create surface area.
Rock Crawling. Very little momentum is needed, hence the title “Rock Crawling”. Traction is a must. Smooth and in control is the name of the game. Choosing lines and knowing your vehicle like the back of your hand are the two main ingredients to successfully climbing rocks in your vehicle. Short bursts of momentum followed by stops and adjusting your line, with assistance of your spotter (someone outside the vehicle to guide you).
Descending slopes. Momentum is the key again. Keep your tyres moving and pointing in the direction of the line you want to take. If your tyres lock up, and you start sliding there’s only one thing to do, and its the opposite of what you want to do. Hit the gas (accelerator), just a little, to regain traction. The wheels should spin at the same speed as the vehicle moving down the hill. Don’t brake !!! This is the same in loose rocks, sand, mud, snow and ice.
River crossings. Yet another example of momentum. Select your gear, start slow then speed up slightly. This creates a “bow wave” in front of your vehicle, which keeps the water out of your engine bay and helps suck the vehicle through the water. A “Car Bra” (tarp like cover across the front of your vehicle) assists in keeping the engine bay dry, and aids in creating a bow wave. Select a lower gear and keep the engine revving through the crossing. BUT walk the crossing first. If the currents too strong to walk safely, then keep the vehicle out of it. Check the depth against your vehicles capabilities. A vehicle with a snorkel air intake will be more equipped for deeper water. Check for rocks, logs or uneven surface that might interfere with your vehicles momentum.
That’s about it from me. Safe and fun 4wding 🙂
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