Today’s trucks are amazing machines. They’re built to comfortably handle highways, but are just as adept once your turn off the pavement and onto the dirt. And, really, what’s the point of 4×4 if you’re not actually going to use it, at least occasionally? But simply going off-road isn’t as simple as it sounds. It’s an adventure that can be challenging and confusing, especially if you’re not prepared. To help remove a little of the worry, we talked to some experts and asked them to explain some of the basics of heading into the wilderness on four wheels.
1. Understand Your Vehicle
Your truck has a number of key systems that play a role off-road. It’s important to understand them, and what they do.
Traction Control: Most modern 4×4 vehicles will have some level of traction control. Depending on what conditions the vehicle was designed to conquer, it could have a simple on/off setting, or a complex system with multiple settings programmed for different traction situations. No matter the system, traction control uses either the brakes and/or the 4×4 mechanicals to limit wheel slip and ensuring torque is being transferred from the tire to the trail. “Traction control tells the onboard computer how to monitor wheel spin and it will brake accordingly to keep the vehicle moving forward,” adds Clay Croft, Creator and Expedition Leader of Expedition Overland. Since there are so many kinds of traction control systems, we encourage you to read up on yours and its many settings in your owner’s manual.
4WD High vs. 4WD Low: Low and High speeds refer to the gearing of your transfer case. 4WD High is what you drive around in day to day. It allows for better top-end speed but lower torque to the wheels when stopped. When you go to 4WD Low, you have more torque on low-end speeds, but your top speed is maxed out pretty quickly. “In short: when you need a lot of low-end power at low speeds on the trail, go to 4WD Low,” Croft says. “When you need to travel fast and keep momentum, you need to be in 4WD High.”
Locking Differentials: A locking differential essentially locks the turning of the left and right wheel together. In normal on-road driving, the wheel on the inside of a corner turns more slowly, as it travels less distance than the outside. In this instance, you’d want the wheels to turn at different speeds. In an all-wheel-drive system, the computer is constantly making adjustments, shifting power to where it’s needed most. On the trail, however, this inconsistent speed between the left and right sides can lead to a loss of traction, as the power will go to the wheel with the least resistance — often the wheel that’s slipping or not getting traction. That’s why you want the ability to go full-time 4×4. Doing this forces both wheels to spin at the same rate, ensuring the power remains with the wheel with the most traction. In the old days you had to get out and manually lock the hubs, but most new 4x4s allow you to lock the differentials using just a button push. “If you can buy a vehicle with a factory locker in it, you are ahead of the game as a novice getting into this world,” said Croft. “Being able to get into a vehicle that has a locking differential in it is a huge plus for the off-road capability of that vehicle.”
2. Do You Need Any Special Equipment?
Tires: Getting a good set of tires to match the most common types of surfaces and terrain that you’re going to encounter is essential. Tires are what ensure traction between your vehicle and the terrain. Their importance cannot be overstated. No matter how stout your rig, if it doesn’t have good tires, it’ll be feckless, and mud tires are different than tires for sand and rock. We suggest you go to a local tire shop and talk to some experts.
Suspension: Don’t make the common mistake of getting a cheap body lift kit. Believe it or not, a fundamental element to off-road vehicle reliability is the shock absorber; it’s the thing that takes all the abuse of the trail and helps to not translate it to the vehicle or driver. Think of suspension as one of your biggest foundational elements to building your vehicle, because, as you go to add new things — a drawer system for organization, for example, or a rooftop tent — you’ll burden the suspension even more. And the more your suspension can handle, the easier your trek will be.
Bumpers: Sometimes referred to as bull bars, aftermarket front bumpers protect the front of your vehicle from rock, tree, brush, and animal strikes, as well as other unavoidable trail obstacles. Off-roaders might also consider a back bumper, depending on what sort of driving you’re doing. A lot of aftermarket bumpers allow you to relocate the spare tire from underneath the vehicle and put it on the back of the vehicle, which, in the event of having a flat tire or being stuck in the mud hole and needing to swap that tire out, ensures it’s not buried under your vehicle when you need it.
Maxtrax: Designed by Australian Brad McCarthy, this is a traction device that goes under your wheels and allows you to crawl out of a hole by regaining traction and momentum. When you lose either traction or momentum, you’re more than likely going to get stuck or lose control. And when you start to lose traction, often you can’t regain the momentum essential to getting your vehicle going again. Maxtrax help you regain traction, to get up out of whatever you’re stuck in, and give you momentum back.
Winch: A winch is one of the first things that people mention: I need a winch if I’m going to go out in the back country! And they’re not wrong; it is an essential active recovery system. That said, winches require some pretty specific skill sets to use safely, and you’ll need some training to operate one effectively. A winch is invaluable when a vehicle is in a precarious situation, and when slow methodical recovery needs to take place. Bear in mind, there are a lot of cheap winches out there. As tempting as it might be to purchase an inexpensive one, the last thing you want is a cheap winches failing on your right when you need it most. So invest in a high-quality winch. It’s worth the money. Because you might not need a winch often, but when you do need it, you need it bad.
Snatch Straps: Snatch straps are a dynamic recovery strap, which is different than a tow strap. Think of climbing ropes; you have static and dynamic lines. A static rope is good for rappelling because it doesn’t stretch. A dynamic rope, however, is made for lead climbers; when they fall, it stretches and absorbs the energy of the fall. Snatch straps use that energy-absorbing stretch in reverse. “The recovery vehicle will back up with a little bit of momentum and load the stretch into that snap strap,” says Croft. “That energy that is now stored into that snatch strap. It will pull and release a vehicle out of the mud or the snow or whatever. It’s not a jerk; it’s dynamic.” This tactic should not be used with tow straps, though, as they do not stretch. Also, do not try to tow a stuck vehicle by attaching to a trailer hitch ball. They will snap and go flying off like a bullet.
Snorkel: If the nose of your vehicle is going into deep water, you run the risk of injesting water into the engine through the air intake and ruining it. Three pumps of a water-filled cylinder will total an engine. A common way to mitigate water ingestion is to equip your vehicle with a snorkel, which draws in air from near the roof of the vehicle.
3. Are you Prepared for Worst-Case Scenarios?
First-Aid Kit: A basic first-aid kit is important to carry. Though the kit won’t be able to solve all first-aid needs, a good one will have what you need to stop blood loss, patch and clean simple wounds, and tide you over until help arrives.
Seat-belt Cutter & Glass Breaker: There are scenarios in which you may need to cut your seat belt, break a window, and make an emergency exit from your vehicle. “I keep the Benchmade Houdini in the ashtray of all my vehicles,” Croft says. “Ashtrays aren’t used much these days and it’s an easily accessible place, if I should need to get out of my vehicle in a pinch.”
Fire Extinguisher: The last thing you need is for your rig to burn to the ground when you’re out on the trail. Affixing a fire extinguisher in the cab is an easy way to prevent fire damage. Plus, it looks cool.
Warm clothes: “Prepare your vehicle for the conditions you might encounter,” Croft says. “You will need to have the adequate clothing to be able to survive 24 hours outside the vehicle.” Even though your truck will have heat, if the engine isn’t running or a window breaks, you will be exposed to the elements. This means more than a rain layer — bring cold-weather insulation as well. It’s never bad to keep a couple blankets in the back or under a seat.
Food & Water: Always carry enough food for the maximum occupancy of the vehicle — even if you’re not hauling more than one passenger. The minimum should be at least one granola bar and one bottle of water per seat in the car. More is always welcome. “Iodine pills are also a good thing to carry,” Croft adds. “They don’t take up any space and can increase your access to drinkable water.”
4. Be Fully Aware of What You’re in For
Prepare Your Recovery: You need to think ahead and prepare for recovery, should you encounter any problems. Have a plan for if you get stuck, and what you’re going to do to get out, because that’s going to aid in when you decide to call it quits. Another key: once you realize you’re stuck, stop. Don’t keep spinning, that just makes it worse. You’ll know when you’re about to get stuck when you’re applying an even amount of throttle and you’re slowing down or losing momentum. As soon as you realize you’re losing momentum, stop the vehicle; don’t wait for it to get stuck. If you stop before it sticks on its own, it’s going to make the recovery much faster. Make sure you know where your tow strap is. Locate trees, etc. to which you can hook your winch. And have your Maxtrax easily accessible.
Airing Down: The best off-roaders — the people who get into places where other people can’t go — understand how to maintain traction. One quick way to help maintain traction is to air down your tires to around 20 to 25 psi. Airing down your tires increases the overall length of the tire tread in contact with the ground by 80 percent. Not only does airing down increase the traction patch, it also allows the rubber to transform to the shape of the ground, giving you more bite into whatever surface you’re dealing with. That pertains to rocks, particularly, as well as mud and other slippery surfaces. When you get into tricky surfaces like very deep mud or snow, lengthening the tread by airing down increases your float — the ability for your vehicle to sit on top of the surface, versus digging down and just getting stuck.
Activating Lockers: Remember that locking the differentials is critical to traction in slippery conditions — it essentially forces both wheels to turn at the same rate.
5. Do You Understand the Different Kinds of Conditions?
Mud, Sand, and Snow: Though seemingly distinct conditions, in terms of traction, mud, sand and snow are handled pretty much the same way. As such, many 4×4 makers will have a single traction control setting dedicated to all three.
That said, let’s focus on traversing mud, which can be the trickiest of the group. “First there are a couple things that you need to consider: How deep the mud is and how far you have to travel through it,” Croft says. “If it’s really deep and really far, you may not want do it at all. If it is within what you think you’re capable of driving, these are the things to do.” Air down to around 20 pounds of pressure. Then put your vehicle in 4WD high and turn traction control off. If you can select a gear, choose a higher gear so that you can toss more mud away and allow your mud tires to self-clean.
“Typically any off-roading, I would recommend going in four high,” says Filip Tomik, 4×4 Systems Development /Calibration Engineer for Ford. “Four low is a unique 4×4 setting and it’s predominantly used if you are doing a lot of sand dune driving.” To tackle any of these three conditions, you’re also going to need a lot of momentum, so you don’t want to be in too low of a gear. For sand, as with mud, it’s all about managing horsepower. So you want to put your vehicle in a position to maximize the horsepower and get through the tacky stuff. “In deep sand, you’d think that 4 Low is ideal,” added Tomik.”But actually you want 4 High, because when the sand starts grabbing the side of the tire, you start taxing the power train very quickly, which will start giving a lot of torque to negotiate the terrain.”
Rock: “When you get into rock, it’s more than likely you’re in what’s called a ‘crawl situation.'” says Croft.”You need to be methodical and precise with the movement and the power and the traction of the vehicle. If not, you’re going to get hung up on something. It’s important to keep speed low, because you could cause vehicle damage from something that hits your vehicle.”
So, air down and put the vehicle into 4WD low. Then pick a line, knowing which one best suits the approach, breakover, and departure angles of your vehicle. You also need to know the height, width, wheelbase of the rig, and the clearance of your differentials. If you don’t know these off-hand, your owner’s manual should specify. If you have an adjustable suspension, raise it up. Also, if you can select a “Rock” setting on your traction control, do that as well. As you roll into the rock, use a very light and consistent throttle. Managing the power with a delicate foot is the key to success in rock. Because you’re in a really low gear and the power is very responsive, you need to relax and slow down how you manage the throttle and keep it really smooth for a precise crawl.
Water fording: “Water fording is one of the most dangerous things that you could do to your vehicle…and potentially to you, so it needs to be done correctly,” Croft says. First, walk into the water source — especially if you can’t see the bottom. At a minimum, you need to have a clear understanding of its depth and what’s under the surface. The best way to do that is to check it out with your feet. Once you know how deep it is and what’s underneath, you can make a plan to cross. But respect its power: Two feet of rushing water is enough to sweep a car away.
When you’re ready to go, angle the truck slightly upstream. When you enter the water, you’ll create what is called a “wake bow.” You’ll then want to keep enough speed to maintain the wake bow, as it effectively lowers the level of water around the sides of your vehicle. As you drive across the water, it will push you downstream a little bit, so plan the drift on where you want to get out.
Finally, if the water’s deeper than your grill, you’re going to want a snorkel. So study the route ahead of time.
6. A Few Final Things to Consider
Be Cautious of Whip: On difficult terrain, try to keep your thumbs outside the steering wheel, to account for something called “whip.” If the wheel is suddenly snapped in one direction or another, it can hurt your wrists, or worse, break your thumbs. Keep in mind this is mostly a problem in vehicles without a power steering damper box. Generally speaking, newer cars with damper boxes won’t suffer whip.
Don’t Over Steer: Try not to over steer when in ruts and on angles. When one side of your vehicle is up on an incline but the other is on flat ground, it feels natural to counteract the weight shift or unnatural lean by steering up toward the incline. Try to avoid it, as keeping the wheel straight is safest. Also, there will be times when your tires are locked into ruts previously cut by other vehicles. These ruts will be weirdly cut and cause your wheels to wander to the right or the left. Do not, however, let the steering wheel wander to the left or right. Even though the vehicle is still tracking straight, due to the ruts, your steering system could be at full lock. The issue there is that as soon as you leave the rut and fully regain traction, your vehicle might steer sharply to one side or the other, leading you into a tree, rocks, or other trail impediments.
Left Foot Braking: If you’re going to be doing lots of off-roading, it’s a good idea to master a technique called left-foot braking. And it’s as simple as it sounds. Keep your right foot on or over the accelerator pedal and apply the brakes with your left foot, rather than using your right foot for both pedals, the way we were all taught. Why? Because it can save you precious seconds and also give you a lot better vehicle control when you’re in rocks or other technical terrain.
This technique can also be used to apply power more evenly. You can use your right foot to keep your engine at 3,000 RPM and use the slow release of the brake with the left to apply that even level of torque to the ground. Utilize this technique sparingly, however, as you can burn out the brakes.
C.A.R: “This acronym was taught to me by the famous off-road racing driver Ivan Stewart. It stands for: Comfortable, Accurate, and Relaxed,” Croft says. What’s it mean? If you can comfortably drive down the road in a relaxed enough manner to keep a cup of coffee in the cup holder, then you know that you are within the vehicle’s and your capabilities and you’re not in danger of hurting the vehicle or yourself.
* This article is part of The Code, an editorial partnership between Car and Driver and Ford F-150.
This story originally appeared on Road and Track.
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