We get letters from folks who are at a loss about how to outfit their 4x4s for a particular 'wheeling environment. Well, we're happy to help out. Part of the reason that we 'wheel in remote areas of the world is to gather information about how four-wheel-drive enthusiasts adapt their vehicles to specific needs and use them to travel in harsh environments. When we come back, the knowledge we've accumulated, along with some very unusual ideas and applications, gives us all a better understanding of what it is that brings us togetherfour-wheeling.
When you consider taking your four-wheel-drive vehicle into challenging terrain you'll notice that there is one common denominator that is very important: traction. Without it you ain't going anywhere, and depending on your situation, lack of traction could be serious, even life-threatening. In one recent Four Wheeler jungle excursion, monsoon rains completely stranded several vehicles. This developed into a life-threatening situation, since we had run out of food and water after being trapped for several days in the relentless downpour. Had our vehicles been equipped with the proper tires, a locking differential, and a winch, the situation would have been a whole lot easier to deal with.
So what we'd like to do is give you a few very simple but important tips on how to prepare your rig for extreme conditions to help you overcome the challenge of 'wheeling through the Big Four: mud, snow, sand and rock.
Tires with open, gnarly tread are what you want here. The more open the tread is, the more the tire will clean itself of sticky mud as it rotates. Obviously, you want horsepower because without that you won't be able to keep your big ol' tires rotating in deep, sticky mud and if they don't rotate, they won't self-clean. Also, you want the tallest tire you can get under your rig's fenders. Depending on the weight of your rig and the consistency of the mud in which you run, you may want to watch going too wide on a tire because (when the mud hole you're addressing isn't too deep and the mud not too gooey) it is helpful to let the tire sink so that it can get a grip on the mudhole's bottom. Mud is heavy, so bulling through it requires horsepower. That extra weight and horsepower also require a driveline healthy enough to turn those big ol' mud tires. The other thing you want to do in mud is maintain momentum. Oftentimes, to stop is to get stuck.
When that happens, the single most important piece of mechanical equipment that will save your butt is a winch. If you don't have a winch to get yourself out of a jam, locking or limited-slip differentials may be your only salvation next to your buddy's tow-strap. Try a Detroit Locker or ARB Air Locker in the rear, a Truetrac or Auburn limited slip in the front, and you'll be surprised how well you'll do in the mud. But effective tires are the place to start. Many experienced 'wheelers believe that the best all around hard-core mud tires are Boggers and Super Swampers.
SNOW AND ICE
During a recent trip to Iceland, the first thing we noticed about the rigs over there was the huge tires they were using. Because they 'wheel over very deep snow, new as well as old daily drivers were outfitted with 35- to 44-inch tires. For on-road use, narrow snow tires that cut through the snow down to a hard surface might be the ticket. But the key to successful off-highway snow driving, our Icelandic experts told us, is maintaining flotation and a low center of gravity. For this, the Icelanders have developed a relatively simple method of applying huge tires without lifting their vehicles much at all. Instead, they cut out the fenderwells and install huge custom-made fender flares.
A good idea for travelling in extremely cold conditions is having selectable fully-locked lockers at both ends. It's also helpful to have an onboard inflation system for your tires. The one we saw in Iceland could be automatically controlled from inside the vehicle, enabling the driver to adjust his rig's tire pressure on demand. To the best of our knowledge, this one-of-a-kind version from Arctic Trucks in Iceland is not available anywhere else, so if onboard inflation sounds like a good idea, you'll have to engineer it yourself. Otherwise bring a compact air compressor.
As always, power is critical in the snow, so apply it carefully. Traction is easy to lose and, once lost, difficult to regain. Use low revs, a light foot on the gas pedal, and when possible, a higher gear than you ordinarily would select. Be equally careful with brake applications and steering inputs.
When it comes to driving in sand, wide, aired-down tires offer the most advantage. Tires with open tread work well, but 'wheelers who spend most of their time in the sand often install paddle tires to get the best possible grip in the soft, shifting sand. You will still get stuck, however, and you'll likely do it while trying to get to the top of a sand bowl. When you're heading toward the top of a dune and you feel your vehicle bogging, just point the nose back downhill and keep your foot on the gas. Lift, and you'll be stuck.
Flotation, light vehicle weight, and lots of horsepower are critical elements. The less flotation you've got and the more weight, the more horsepower you need. And as in other situations, maintaining momentum is extremely important. If you're alone and get stuck, a winch and a sand anchor will come in handy. There are several types of sand anchors available on the market, and some 'wheelers even fabricate pretty decent ones in their own shops. When you're in a bind, bury your spare tire and use that as an anchor. When we were in Australia, we saw sand anchors of all shapes and sizes bolted on the backs of 4x4s. A good all-around anchor is the new RW 11000 "military-size" Pull Pal which is rated up to 11,000 pounds.
Maintaining traction on rocky surfaces has a lot to do with the condition of the rock itself. If you're attempting to traverse a loose, rocky section, large, wide tires with an aggressive tread are what you want. Air them downway downso that your tires' contact patch can more easily conform to the profiles of the rocks you're driving over. But be aware that low pressure means sidewall bulge, and sidewall bulge can greatly increase your chances of rock cuts on those sidewalls. So bring a spare and be prepared to use it. Horsepower is less important on the rocks than it is in other situations. But what's important here is picking your line. While you're watching where your tires are going in the next 10 feet, you've also got to keep an eye on where they'll be going in the next 20 feet after that. Be thinking of placing your tire contact patches where the most grip can be found.
What you also need is a locking differential, a transfer case with a low-range ratio that is very low (some aftermarket units are as low as 4:1, while OEM transfer cases more typically are between 2:1 and 3:1). And if your goal is to run hard-core rockcrawling trails, a good flexy suspension plus great tires and lockers front and rear are a must. As you may already know, there are many companies that offer aftermarket suspension systems. Among them, long-travel suspension systems work great on vehicles such as Jeep TJs, providing extreme amounts of flex that can result in less wheelspin, hop or bounceand that means more traction.