4-Wheel-Drive Basics: 6 Ways To Conquer Any Trail
November 16, 2017
Use these six off-road driving quick-tips to tackle mud, rocks, snow, sand and water crossings with ease in the 2018 Ford F-150.
The rutted two-track that leads to the hunting lodge. The sandy trail winding down to a favorite fishing spot. The ski cabin at the end of a seldom-plowed road. You don't want a four-wheel-drive truck just so you can stand out in a crowded valet parking lot. You need a 4x4 to get deep into the backcountry and hunt/fish/ski/hike or any of the other adventures planned for your time away from the daily grind.
In fact, when you're really using a 4WD truck the way it was intended, getting to your outdoor destination is an adventure in itself. But there's the good kind of adventure — the thrill of making it through the mud, between the trees, over the rocks — and the other kind, the kind that ends with a long walk for help.
Fortunately, today's 4x4 trucks, including the new 2018 Ford F-150, come straight off the showroom floor with a remarkable amount of off-road capability. The right optional upgrades — like the available FX4 Off-Road Package — can enhance those capabilities further.
Still, a successful trip off the pavement depends in large part on the skill of the driver and his or her ability to read and negotiate the terrain. Off-road driving is not a "one-size-fits-all" activity. The techniques you need on rocks, for example, will only get you mired in sand.
Here are six off-road driving quick-tips that can help you handle the rough stuff where the pavement ends, and learn about the specialized features available on the new 2018 Ford F-150 that turn tough terrain into that good type of adventure.
What makes a 4WD pickup different from conventional two-wheel-drive models is the 4x4's transfer case and driven front axle. True to its name, the transfer case can send engine power to the rear axle only or to the front and rear axles.
There are two different kinds of transfer cases used in the Ford F-150. XL and XLT trims have a two-speed transfer case, with High and Low ranges (indicated by 4H and 4L on the transfer case knob). Trucks with Lariat trim and above also have an Automatic 4WD mode (4A).
The Automatic mode uses vehicle sensors to monitor traction. A clutch in the transfer case engages the front wheels as needed (with no driver input) when it senses traction loss. Automatic mode can be used on pavement as well as off, making it handy for rainy and snowy conditions or on road surfaces that vary from firm to slippery and back again.
High range makes a mechanical link through the transfer case between the front and rear axles. This is the setting to use on unpaved or unmaintained roads, in the sand, and on easy 4WD trails. It should be used off the pavement only to prevent driveline binding when the front and rear wheels travel at different speeds (while cornering, for example).
When the going gets gnarly — steep hills on loose soil, rocky trails, thick mud — it's time to turn the knob to 4L. In Low range, transfer case gears multiply the engine's torque going to the wheels, improving the truck's ability to climb over and through rough terrain. Low range is for slow-speed driving only, typically 20 to 25 mph or less.
On the subject of gnarly, an F-150 that spends extended time in the outback will benefit from Ford's available FX4 Off-Road Package. Many other manufacturers offer "off-road" trim levels that are often no more than decals and rubber floor mats. The FX4 Off-Road Package is a suite of truly functional upgrades, including an electrically operated, locking rear differential (to maximize rear-wheel traction); skid plates under the fuel tank, transfer case, and front differential (to protect those components); Hill Descent Control (for safe downhill crawling); and specially tuned shock absorbers (for a controlled ride even under the harshest of conditions).
1. Driving Tips: Rocks
On a trail with lots of rocks, exposed roots, low stumps or other obstacles, driving at a leisurely walking pace allows time to precisely pick your way through the terrain. Dial in Low range for optimal torque to power over what you can't drive around, and turn on the electric rear diff lock (if the truck is so equipped) so that both rear wheels are working equally to drive the truck forward.
When navigating rocks, keep your vehicle's approach and departure angles in mind. These terms refer to the angle between the tire and the lowest hanging part of the front or rear of the truck, called the "overhang." You don't need to know the exact measure of that angle, but visualize it as you roll up to an obstacle to consider whether the tire or the overhang will make contact first.
The F-150 has a very short front overhang, giving it a good approach angle. And while it seems obvious, remember that both ends of the truck need to clear a trail obstacle. While lining up for the next rock, it's easy to forget that the back of the truck still has to make it over the last one. Drivers need to remember to really tip-toe over the rock with the back end, so the rear doesn't come crashing down on that rock as you drive away.
2. Driving Tips: Sand
Flotation and momentum are your best friends in sand. Flotation comes from a wide tire footprint in order to "float" over the sand's surface and not dig in. Factory all-terrain tires offer an excellent footprint for all-around off-roading.
From a speed standpoint, sand driving is the opposite of rock crawling. Keep the truck in High range and maintain a good, safe head of steam until the truck is on more solid footing. If you must stop on the sand, try to find a spot where you can park with the truck pointed downhill, so gravity can help you get moving again. If the tires start to dig in, don't just jam on the throttle, as that will likely bury the truck to the axles. As soon as wheel slippage is felt, stop and find some sort of solid traction aid to put under the tires. ATV ramps, wooden planks, even floor mats will help.
3. Driving Tips: Mud
A big difference between sand and mud driving: wheel-spin will not necessarily trap a truck. The opposite can be true. When forward momentum slows and wheels start to spin, stay on the throttle and turn the steering wheel back and forth, allowing the front tires to look for purchase.
4.Driving Tips: Snow
As with driving in sand and mud, flotation helps get a truck down snowy roads, just as snow shoes better distribute weight than boots. But while speed and momentum are plusses in sand and mud, they can quickly turn dangerous in snow, due to the extremely low friction coefficient of the snowy road surface.
Drive as if there is a raw egg between your foot and the gas and brake pedals. Make slow and deliberate movements with the steering wheel. If you turn too sharp and the front end doesn't follow where the wheels are pointed, back off the throttle and unwind the steering wheel a bit.
Driving in the snow is one of the few off-roading situations where a locked rear differential may actually hinder forward progress, because the two rear wheels working (too) hard could cause the rear end to slide out.
Four-wheel drive does provide better traction in the snow than 2WD, but it doesn't mean you get an automatic pass when it's time to put on snow chains. Carry chains and be prepared to use them where needed and where permitted — on both ends of the truck.
5. Driving Tips: Water Crossings
Fishermen know there can be surprisingly deep holes in an otherwise shallow riverbed. Don't cross a stream before checking the depth first. The term used by many off-road enthusiasts for sucking water into an engine is "hydrolocking ," otherwise known as "time for a new engine."
And while high-speed blasts through the water may look dramatic on film, churning up the water like that wreaks havoc on the stream's ecosystem. As with crawling through rocks — which, in effect, is the case here, except the rocks are underwater — walking pace is the best way to get across without harming the stream or the truck.
6. Driving Tips: Hills
Successfully ascending and descending hills requires many of the same techniques as rock crawling: Transfer case in Low range, rear-end locked, careful tire placement on rocks and obstacles, mind your approach and departure angles, travel only as fast uphill as necessary in order to maintain momentum. When encountering a rock shelf (going either up- or downhill), approach it at an angle, so the truck climbs or drops off with one wheel at a time.
Cresting a steep hill can be nerve-wracking — from behind the wheel all that's visible is sky and not where the trail drops away. Getting out to look may not be a viable solution, since it may not be safe to park and leave the truck.
Walking the hill before driving over it is one answer; another is to make use of Ford's available 360-degree camera with split-view display. It's available for the F-150 as part of Ford's Technology Package. Cameras located in the truck's grille, tailgate, and under each outside mirror transmit images that are stitched together on a dashboard screen, providing a clear view of the trail all around the truck.6 Steep descents can also take a toll on a driver's nerves, as the sharp nose-down angle often makes the truck "feel" less stable than it really is. Riding the brake to control downhill speed is not a good idea, as it's too easy to lock the wheels, causing the truck to slide on loose soil.
The available Hill Descent Control, included in the FX4 Off-Road Package, will automatically maintain the downhill speed you set with no additional pedal input needed, so you can focus on just steering down the hill.
A truck without Hill Descent Control can approximate the same effect with the transfer case in Low range and the transmission in First. The gear reduction will slow the truck to an absolute crawl, though gas or brake pedal input will still be required to alter that speed.
To see the new 2018 Ford F-150 in the field on action-packed fishing and hunting adventures, visit The Ford Outfitters.