4 X 4 BASICS AN INTRODUCTION TO OFF ROAD DRIVING
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TABLE OF CONTENTS
Torque, Traction, and the 4WD System
5 CROSS-AXLE
8 Shifting Gears in a 4WD
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Mechanical Sympathy
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Aborting a Hill Climb
23 RECOVERY OPERATIONS
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By taking the time to understand how your 4-wheel drive (4WD) vehicle works, you will be able to think your way through problems and negotiate terrain efficiently rather than trying to force your way through and damaging your vehicle. Once you know the basics of your 4WD system and how to use it to drive off-road, you will be able to get where you need to go when performing your job duties. You will also be able to venture to beautiful and exciting places you never knew existed. The modern 4WD is a very capable off-road vehicle. You will be astonished at where you can take it. Unfortunately, manufacturers allow advertisers to show these vehicles driving in a manner that makes you cringe. Who would want to drive their expensive vehicle in this manner, risking damage? With the right knowledge and attitude, you will drive in a manner that will not damage your vehicle, your nerves, or the environment. Driving with “mechanical sympathy” simply means to treat your vehicle with loving kindness. You will find that you often run a greater risk of damaging your vehicle driving to the store than when driving off-road.
OFF ROAD DRIVING
OFF ROAD DRIVING
SAFETY
Safety is the most important consideration in any risky endeavor and driving is a risky endeavor. Contrary to what many lawyers and civil juries think, it is not possible to eliminate all risk from our lives. Operating any type of vehicle is a dangerous activity. Your job is to manage the risk by learning as much as possible about the operation of your vehicle and taking reasonable precautions. If you encounter a situation or obstacle that you are not sure about, then get out and assess it before proceeding. The saying we use is, “When in doubt, get out.” This is how you should manage your risk. The only way to eliminate risk is to simply not drive. Because this is not an option, let’s continue.
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TORQUE, TRACTION, AND THE 4WD SYSTEM
Understanding the relationship between torque and traction is necessary to effectively drive in a variety of off-road conditions. “Torque” is the amount of twisting force supplied to the wheels. “Traction” is the amount of friction between the tire and the road surface. If more torque is applied to a wheel than the amount of friction present between the tire and the road surface, then the wheel will lose traction and spin. The differential allows the wheels to turn at different speeds and equalizes the torque between the wheels. This can be detrimental in off-road situations where one wheel has traction and one wheel starts to slip. When one wheel on an axle loses traction, less torque is required to make it turn. Because the differential equalizes the torque, less torque will then be present at the wheel with better traction. The torque present at the wheel with traction may not be enough to move the vehicle. This is where 4WD comes in.
On a part-time 4WD system, there is a transfer case that allows torque to be sent to both axles. The drive shaft going to the front differential and the drive shaft going to the rear differential are rotating at the same number of revolutions per minute (RPMs). The differentials then split the RPMs between the two wheels. The sum total RPMs of the wheels on the front axle is the same as the sum total on the rear axle. If one wheel loses traction, then you will still have torque present at the other wheel on the same axle because the wheels on the axle must turn at the same total RPMs as the other axle. When you turn the vehicle, the wheels will start turning at different RPMs. Whichever wheel has the least amount of traction will be dragged or pushed across the ground due to this equation. You can hear this happening when offroad, but if you are on pavement with a lot of traction it will be very difficult to turn as you fight against these forces.
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CROSS AXLE
Weight is a component of traction— the more weight on a wheel, the better traction it will have. When in uneven off-road environments, it is common to get into a situation where diagonal front and rear wheels lose traction. This is known as a “cross-axle” situation.
cause these diagonal spinning wheels are spinning at the same RPMs. Because the differentials are equalizing the torque, the same amount of torque required to spin the wheels without traction will be present at the wheels with traction. If this is not enough to move the vehicle, then you are stuck.
Cross-axle situations occur when you have weight off of one wheel and weight off of the opposite corner wheel. For example, you drive over holes that coincide with the left rear and right front wheels. This leads to a condition where (with open differentials) the wheels in the holes will lose traction and spin because there is very little weight on them. The sum total of RPMs on the front axle is equal to the sum total of RPMs on the rear axle be-
With open differentials (no locker) you can apply the brake with your left foot while also applying some throttle. Because torque will be required to overcome the brake, you will get more torque to all wheels, including the ones with traction, which may be enough to get you moving again.
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CROSS AXLE
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ALL-WHEEL DRIVE (AWD) A vehicle with AWD has a differential connecting the front and rear drive shafts. This allows the drive shafts to rotate at different rates of speed. Because of this center differential, the sum total RPMs of the front wheels do not have to be the same as the sum total RPMs of the rear wheels. This makes it easy to turn and you get the benefit of torque going to all the wheels. But when you are on very uneven ground off-road and one wheel loses traction, the differentials will go to
work equalizing the torque and the wheels with traction will have the same amount of torque present as the one spinning wheel. AWD is great for fairly even road surfaces with low traction but it is not good for the very uneven surfaces encountered in off-road situations. Most AWD vehicles do not have low range gears like 4WD vehicles, but there are a few exceptions such as some models of the Mercedes Sprinter Van.
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LOCKERS When a differential is locked, the wheels on the same axle can no longer turn at different RPMs and the same amount of torque will be present at each wheel. Differences in traction between the wheels no longer have an effect because the wheels must turn at the same RPMs. Some, but not all vehicles have differential locks. Do not confuse differential locks with hub locks! Hub locks secure the front wheels to the axle when the vehicle is shifted into 4WD. These are automatic on most vehicles, but some still have manually locking hubs. Check your owner’s manual.
TRACTION CONTROL Some vehicles have a computerized system to help with traction. Each manufacturer has a different name for it, but they work in the same manner. The computer will pulse the brakes on the wheels that are spinning. Because more torque is required to overcome the brake pulse and the differentials are equalizing the torque, more torque will be present at the wheels with traction during the pulse. This helps get the vehicle moving again.
FULL-TIME 4WD A full-time 4WD gives you the best aspects of 4WD and AWD. When the vehicle is not in 4WD it is AWD. Rather than a transfer case linking the front and rear drive shafts, there is a differential. This allows the drive shafts to rotate at different RPMs. You can turn easily because the sum total of RPMs at the front axle does not have to equal the sum total of RPMs of the rear axle. When the vehicle is shifted into 4WD, this center differential is locked, making it work just like a transfer case in a 4WD. Full-time 4WD vehicles have low-range gears.
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OPERATING YOUR 4WD SHIFTING GEARS IN A 4WD The vast majority of 4WD vehicles have high-range and low-range gears. Lowrange gears give you more torque and are easier on your drive train when in difficult off-road environments. Think of a 10-speed bicycle. When you put it in 1st gear, you pedal quickly without going very fast, but you can climb steep hills. This is the same concept as the 4WD low-range gears. You will not be able to drive faster than about 20 mph but you will easily climb hills and negotiate obstacles. If you are on a dirt road that is not steep and has few obstacles, then you can use the 4WD high-range gears. Every vehicle has slightly different features, but you can typically shift into 4-wheel drive high range while you are moving. Your speed needs to be typically less than 50–55 mph. To shift into 4WD low range, stop and put the main gear shift in Neutral. Once you are in neutral, shift into 4WD low-range using the button, knob, or lever for your vehicle. Then put the main shifter back into Drive.
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FINESSE
Think “finesse� when driving off-road. The best off-road vehicle is an overweight, underpowered vehicle with a lot of torque. You are limited by how much traction is available in relation to torque, not by horsepower. Think your way through things; do not just try to throttle your way through every problem. Sometimes it can be a matter of moving a few inches one way or another on the trail or around an obstacle. If you understand how your vehicle works, then you will understand how to thoughtfully solve problems and thereby prevent damage to your vehicle.
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MECHANICAL SYMPATHY “Mechanical Sympathy” means you should treat your equipment with care and respect so that it will serve you well for years. This also means you need to practice finesse when negotiating obstacles instead of trying to muscle your way through. If you are hung up on something, STOP. Get out and find out what is causing the problem. Continuing to try to power through the situation will only lead to breakage.
FRONT END SWING/REAR WHEEL CHEAT When backing up, turning the wheel will cause the front end to swing out to one side. If you were in a parking lot parked between two other vehicles, what would happen if you immediately turned the wheel when backing out? You would collide with the vehicle next to you. This is called “front end swing.” When off-road, watch for obstacles that your vehicle can swing into or even end up straddling that could cause damage to the underside. When driving forward, the rear wheels track inside the front wheels when you are turning. Have you ever seen someone drive into their driveway where the front wheels go up the ramp, but the rear wheel drives over the curb? This is rear wheel cheat, also known as off-tracking. In off-road situations, be careful not to steer around an obstacle with the front wheels only to scrape the rear sidewalls or quarter panel.
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DO NOT STEER WHILE STOPPED
Do not steer when you are not moving. Power steering is a wonderful invention, but it can also break things. You may not know your front wheels are pushing against something and are unable to turn. Steering while stopped, especially in rocks, can break parts because the power steering system gives you enormous mechanical advantage, which supplies great force to the front wheels with little effort on your part. If you feel any steering resistance, stop.
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SURMOUNTING OBSTACLES When you encounter a large rock or tree branch down in the trail that you must drive over, use your left foot on the brake and increase your RPMs. Use the brake to maintain a controlled, constant, creeping speed. This will keep you from hitting the obstacle too fast and from slamming the rocker panels when you come down the other side. If possible, take the obsta-
cle one wheel at a time. Take it slowly and use a spotter (spotting is discussed later) to ensure you have enough clearance. For a manual transmission, put it in 4WD, low-range, 1st gear. You will climb up, over, and down the other side at a controlled and constant speed. With a manual transmission, the vehicle will crawl over with little difficulty.
THROTTLE CONTROL
The best way to finesse the throttle is to brace your foot against the hump to the right of the pedal and twist your foot onto the accelerator. This will give you fine control of your speed. Trying to control speed using the usual heel-on-the-floor method often results in jerky forward progress and unnecessary lunging. Driving on a bumpy road will cause uneven throttle if you don’t brace your foot.
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CLEARANCE
Know how much clearance you have under your vehicle. Usually, your differentials are the lowest part. Know whether they are offset to one side or in the middle of the axle. If you encounter a rock or other obstacle in the trail that is higher than your differentials, consider going around it, or drive over it by putting your wheels directly on the obstacle.
Use the increased clearance of your 4WD to your advantage, but if it appears there is not enough clearance, carefully pick a course of travel that puts your tires on the high spots. Make certain that when your wheel drops off the object you have enough clearance from the rocker panels. The objective is to smoothly cross the obstacle without scraping any part of the vehicle.
WASHBOARDS Roads with washboards can be brutal on your nerves and your equipment. A washboard is caused by the slight slipping of wheels under torque or braking, which causes small ridges in the dirt. Driving at high speeds can be very dangerous. Driving faster over it might feel smooth, but this is because the tires are skipping from ridge to ridge. It will eventually feel like you are driving a hovercraft and can cause loss of control. You may find a speed that is fast and smooth, but driving like this for long periods or on a routine basis will eventually vibrate your vehicle to pieces. You also dramatically increase your chance of tire failure. Slower speeds will help you maintain traction and will be a lot easier on your vehicle. Remember, mechanical sympathy! TheDrivingCompany.com
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MUD Avoid deep mud when possible. Mud can be bad news! If you must go through it, then get out and check the depth and consistency. Thick, sticky mud can be the worst. Deep mud can create a suction effect. Tire chains can be effective in mud if you must go through it. The clay type of mud found in our training area at Hollister Hills is not deep, but it is slick and dangerous. Everything slides in the direction gravity takes it, regardless of where the trail goes.
Returning to the paved road after driving in mud, your tires may feel out of balance and the steering may have a pronounced wobble. This is caused by mud that has caked onto the wheels. Mud on the tires can also reduce your traction like you were still driving in the mud. Do not drive too far before cleaning this mud out with a hose or pressure washer.
ROCKS When traveling a very rocky trail, use 1st gear low-range to better control your speed. Pick a line that will keep your axles flexing as little as possible and do as little steering as possible. Your goal is to keep equal torque to all the wheels as much as possible, which can be accomplished by left-foot braking and by doing as little steering as possible. With manual transmissions, pick a gear that allows for a smooth speed and let the vehicle do the work. Throttle control is key. TheDrivingCompany.com
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SAND Loose, dry sand can be tricky. You will definitely need to air-down your tires to as little as 8–12 psi. This will give you a large enough footprint to “float” you across the sand. You need to keep your momentum going by supplying enough throttle to keep moving but not so much that you start the wheels spinning or bouncing. With some practice, you will find just the right amount of throttle. The type of sand will vary in how much traction you will get. Moist sand is easier to drive on than dry sand. In large dunes, the windward side of a dune is more packed than the leeward side and you will usually
find more traction near vegetation. The key is to search around for the best traction and generally do not spin the wheels. If the wheels spin and you are moving forward, keep going. But if your forward progress stops for even an instant, get off the gas. Do not hit the brakes because you will dig the front in deeper. Driving in sand dunes can be very dangerous and requires specialized instruction. You can get yourself in trouble very quickly if you don’t know how to read the terrain. Large dunes can create large blind spots, so be careful when ascending and descending. Keep your vehicle perpendicular to steep dunes. It is easy to get sideways, causing a rollover. If you have to stop, then try to stop on a level spot or facing downhill. Starting from a stop on a steep hill can be difficult in the sand.
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We have all seen the motorist who ventures into the water accumulated under an overpass after a storm only to find it is roof high. When you encounter water, get out and check how deep it is before venturing across. The deeper it gets, the less traction you get because the tires and vehicle body provide some floatation because they are filled with air. You may need to put the waders on and walk out there to see if there are any deep holes or big rocks that could damage your vehicle.
speed to develop a bow wave in front of the vehicle in order to keep the engine compartment in the trough of the wave. This is a myth. Slow is the way to go! If you watch the engine compartment while driving through deep water, you will see that water comes through the grill and swirls around. There is no “trough.”
If the water has a swift current, then be especially careful. It is easier than you think to get swept downstream. When in doubt, find another way to cross or don’t cross it at all.
Hot vehicle parts like wheel bearings placed in cool water will create a vacuum caused by the change in temperature. This will cause perfectly good seals to suck in water. If your area requires frequent water crossing, then be sure your maintenance people monitor things like bearings, differentials, and transfer case to keep them free of moisture.
Know where your vehicle is vulnerable to drawing in water. Your differentials have vents, your engine has an air intake, and your transmission and transfer case have vents. Some people advocate getting up enough
You can ride the brakes a little with your left foot as you exit the water to expedite the drying process. Your brakes may not work properly until they are dry.
WATER
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SNOW
I hear people brag that they do not need chains because they have a 4WD vehicle. This may get you past the checkpoint for chains, but you should consider putting them on anyway if conditions are bad. You have 4WD but, like every other vehicle, you have 4-wheel brakes. Your 4WD will help you go forward but it will not help you stop faster than any other vehicle. At 20 mph it takes 17 feet to stop on dry pavement, but on ice at 20 mph it takes 150 feet to stop! That’s almost 9x the stopping distance from dry pavement. Even with chains on it will take you 75 feet to stop. Check the owner’s manual for your vehicle. The type of traction devices you put on your vehicle depends on the manufacturer’s recommendations. The type of suspension you have dictates whether you use chains or cables, and which tires you put them on. If you are parking in snowy conditions, then plan ahead. Do not park where you will have to drive up a steep grade when you leave. If your vehicle is fussy about shifting into 4WD, get it into 4WD before you park. This way, you will be ready to go if conditions change after you park. You may also consider putting your chains on if heavy snow is expected before you move again. Toyota recommends not setting your parking brake in freezing conditions. If snow or water accumulates around the parking brake, then it can freeze and prevent it from releasing.
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HILLS
Before climbing a steep hill, you should know what is on the other side. As you crest the hill, visibility will be limited. Discovering there is a cliff on the other side as you crest the hill is not the time to find out. Yes, you may have to get out of your vehicle and walk to the top to see what is or is not there. Remember, spinning wheels have less traction, so easy does it on the accelerator. You should be in low-range, Drive, or 3rd gear. If your wheels slip, then the transmission will shift up, providing less torque. Set your RPMs at a constant rate of 1200–1500 and let the vehicle slowly climb the hill. Many think that you should be in low-range 1st gear, but this gives you maximum torque and the throttle is so touchy that you will probably get wheel spin, which you are trying to avoid. If you find the transmission keeps shifting, then select a lower gear and keep it there. If you encounter a problem on the way up and the vehicle simply won’t make it because the wheels start to spin, then stop! Do not continue to spin the wheels. The vehicle could pitch sideways and roll over. Put the shifter in reverse and slowly back down. Use your sideview mirror or camera to keep the vehicle straight as you back down, and use a spotter if necessary.
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Aborting a Hill Climb Hill aborts are a frequent cause of rollover accidents. Make sure you maintain rolling friction when backing down a hill, which means you must keep the front wheels rolling! If the front wheels are skidding and not rolling across the ground, then you will not be able to steer. Because most of the weight and braking power in your vehicle is up front, it will start to slide sideways on the hill if the front wheels are locked up. Once sideways, it can roll over. To give yourself a little more braking to the rear wheels as you back down, set the parking brake about half way on—not full to cause the wheel to lock. Even if you are backing faster than you want, keep the front wheels rolling so you can steer your way out of trouble. For larger off-road vehicles that have air brakes, a spring brake is used as the parking brake. This spring brake is either all the way on or all the way off, but you can still use it to back down the hill. Just engage it, put the rig in reverse, and apply light pressure to the service brakes. The engine idle should be enough to overcome the spring brake while giving you the control you are looking for. It may be necessary to give it slight throttle to get moving. If you have a feature called “Hill Descent Control” (or “Crawl Control” for many Toyota models), then this is the time to engage it. Get the vehicle in reverse and allow the computer to control your speed back down the hill without skidding. Before you get into a hill abort situation, verify that your Hill Descent Control feature works in the reverse. Practice backing down a hill before you actually need to do it. Find an easy hill and practice. As you get better, find a steeper hill to practice on. Soon you will be proficient and it will be no problem when you actually need to use the technique.
If the engine stalls while climbing a hill, then restart the engine while holding the vehicle with the main brake and the parking brake before getting it back into gear. Do not coast down the hill in Neutral. If you have a manual transmission, then just restart the engine with it in gear. In 4WD low-range, 1st gear, your starter will do the job with no problem. Climb and descend hills while oriented as straight up and down as possible. Getting sideways on a steep hill can lead to a rollover. Never attempt to turn around on a hill. If you encounter another vehicle on a hill, then the vehicle traveling uphill has the right-of-way. Do not be afraid to admit defeat. Do not repeat what you just did if it didn’t work the first time. Do not have your ego invested in that particular hill. If you can’t make it, then choose another route. Stopping and starting on a hill can be a challenge. With an automatic transmission, use your left foot. You want to avoid rolling back when transitioning your foot from the throttle to the brake whether you are starting or stopping; using your left foot will help you avoid that. With a manual transmission, you can turn the key off and on with the vehicle in gear. Some vehicles allow you to start it in gear and some have a switch or button you will need to press to allow this. Some vehicles do not have this feature at all and you must depress the clutch before you can start it. If this is the case, then seriously consider adding this feature. In the meantime, you can use the parking brake to keep you from rolling back. Some people think you will damage your vehicle by starting it in gear. Starting in 1st gear, low-range is not a problem for your starter. We had no issues using this technique in heavy, armored vehicles.
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PARKING
Putting your transmission in Park when parking on a hill can get you stuck. The weight of your vehicle resting on the parking pawl can get it stuck in Park. The pawl prevents the wheels from turning, but if there is too much pressure on it, then you may not be able to move the shift lever.
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Set the parking brake
Put the transmission shift lever in Neutral
Slowly release the main brake until all the weight of the vehicle is resting on the parking brake Put the vehicle in Park Chock the wheels to prevent the vehicle from rolling. When you leave, be sure to do the opposite procedure: Foot on the main brake Shift into the appropriate gear Release the parking brake If you are backing down a steep hill, then follow the hill abort procedure.
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PA R K I N G
Turn the wheels uphill if necessary as you roll to a stop (such as on a shelf road)
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APPROACH ANGLE Because the front and rear of the vehicle hang over the axles, they may drag on the ground. As you approach a steep hill or mound, the front bumper may contact the ground before the wheels can start climbing. The amount of overhang and vehicle clearance determines your approach angle.
RAMP ANGLE When traveling over a large mound or when cresting a steep hill, the center part of your vehicle may contact the ground. If the front wheels have cleared the top and the rear wheels have not yet started climbing, or the top of a hill flattens abruptly, then you risk becoming “high-centered.” This is known as “ramp angle” or “break-over angle” and is a function of ground clearance and the length of the wheelbase. TheDrivingCompany.com
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DEPARTURE ANGLE When on a steep hill, your rear wheels will start climbing or traveling on level ground before the rear bumper has cleared, which can cause the bumper to drag on the ground. This is also a function of the amount of overhang and clearance. This is known as your “departure angle.� The more of the vehicle you have extending past the rear axle the more of a problem you will have with the departure angle.
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SIDE TILT
Most of us have a built-in alarm that tells us when the vehicle is tilting too far to the side. If it feels like it is getting too far over on the tilt angle, it is. Change your angle by taking another track or backing off. Type III fire rigs will have a tilt table side tilt number. You should never get near this number, because this test was done in static conditions on a table. The field will not be so static and other gear may have been added to the rig that could change its tilt tolerance. The Driving Company avoids tilting stock vehicles more than 22 degrees and avoids tilting Type III rigs more than 20 degrees. These vehicles can tilt more than that in optimal conditions but we like to have a margin of error for the driver estimating how much tilt is happening and to account for any weight transfer happening. Water tenders should not tilt more than 10 degrees.
If the vehicle starts to roll, quickly turn downhill, release the brake and press the accelerator to transfer weight and get more level. You may end up stuck, but at least the wheels will be on the ground. Before attempting a side tilt, check out what is downhill. If it is a cliff, find another route. If there is evidence other vehicles have rolled here, find another route. If you can find a route that makes driving with a side tilt unnecessary, take that route. Listen to your internal alarm—it will keep you out of trouble. There is one scenario where you can easily roll over while side tilting. If you are going downhill and turning in the direction of the tilt, it can roll over before your internal alarm goes off and with as little as a 10 degree tilt. Exercise extreme caution on turning downhill from a side tilt!
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Tires
TIRES
A lower tire pressure off-road than when on-road is very beneficial. When you lower the tire pressure, you increase the contact patch, or that portion of the tire in contact with the ground. The exact tire pressure depends on the type of driving surface. Tire pressure of 30–35 lb. works well for stock emergency vehicles for most applications. This will allow you to travel at average speeds on-road and transition to off-road with little difficulty. If you are operating in sand, mud, or snow, it will be much lower. Tire pressure is dependent on your type of vehicle, type of tires, the environment in which you are driving, and the nature of your assignment. For recreational off-roaders, you can air-down to the best off-road pressure for the environment you are in and then simply air-up when you are done. Emergency responders need to find a pressure that allows decent off-road and on-road performance as they may be transitioning between the two. Be careful to not get too much lateral force on tires with very low pressure because you risk running the tire off the bead. It will go completely flat and it is very difficult to get it back on the bead.
Do not air-down dual wheels because the sidewalls will rub together causing tire damage. Some people have tried to airdown dual wheels but only to the point just before they touch. The problem with that is when the vehicle goes over bumps, the tires will flex, causing the sidewalls to touch. SAFETY NOTE: Low tire pressure onroad will result in higher friction, which results in higher tire temperature. Tire failure is more likely when the tires are running hot. Do not try to “performance drive” any SUV. These vehicles are not designed for high-speed performance driving. Attempting to performance drive a vehicle on-road with improperly inflated tires can result in serious injury and vehicle damage. Before returning to the paved road, re-inflate your tires to the recommended pressure. Also, be aware that tires with lower pressure will hydroplane easier on paved surfaces. Check your owner’s manual for recommended on-road tire pressure. Keep in mind that lowering tire pressure also lowers the clearance of the vehicle over the ground. Lower pressure spreads the weight of your vehicle over a larger patch of tire that is in contact with the ground. Because the tire spreads, your sidewalls will be more susceptible to damage.
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SPOTTING
When off-road, the person occupying the passenger seat is a co-driver, not a passenger. The co-driver can watch for hazards by getting out to check the terrain ahead and spot for the driver. A good spotter also knows how to drive the vehicle and understands the principles of 4WD, clearances, and angles.
instructs when the spotter gives the instruction. The driver needs to let go of ego and trust the spotter. Work out hand signals to use for turning right, left, straight, very slow, and stop. The driver should look at the spotter and follow the signals exactly. Teamwork is critical for getting through tricky situations. If there is disagreement, then stop, talk about it, and When using the spotter, the spotter is in agree on a plan before proceeding. charge. The driver should do what the spotter
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RECOVERY OPERATIONS Sooner or later, you will get stuck or you will need to help someone who has become stuck. Sometimes the solution can be as simple as discovering the stuck vehicle is not in 4WD; other times, you will need to break out the winch. The trick is to find the most efficient means to free the stuck vehicle.
of resistance that is causing the problem. When in a rocky environment, move rocks around to remove resistance or solve a cross-axle issue that is preventing the vehicle from moving.
Using another vehicle to free a stuck vehicle can be very dangerous. If you use a chain, tow strap, steel cable, or other means to hook one vehicle to another, then there is the potential for serious injury or damage. If the cable breaks, the loose ends can be lethal. Parts can fly with enormous force causing severe injury or vehicle damage, so you need to take If you are really stuck, then you may need to get out precautions. the shovel and dig it out. You need to eliminate the obstructions in front of or behind the wheels that There are different recovery strategies involving are making it difficult to move. You may need to different types of recovery gear. Use gloves when change the tire pressure. The main thing is to change engaging in recovery operations, particularly when whatever is causing the problem. A few minutes of handling winch lines, recovery ropes, and straps. shovel work can dramatically decrease the amount Make sure the vehicle is in the proper gear. It may be in high-range instead of low-range. In modern, push-button 4WD vehicles, you may only need to put the shifter in Neutral, shift into 2WD high, then back into 4WD Low.
The most important piece of equipment you have is your brain. Check your ego and don’t be afraid to admit defeat and try a different route. Having the right attitude behind the wheel of any vehicle will help keep you out of trouble. A little humility is a good thing.
EQUIPMENT
inspection. After leaving an off-road environment, inspect the vehicle for any broken or loose items. Also make sure you air your tires up to road pressure if you had aired them down.
The most important safety equipment you have is your seatbelt. Seat belts are the single most effective You should make sure you have all the necessary occupant safety device in any vehicle. Airbags are equipment with you and that it is in good working designed to work in conjunction with seat belts; airorder. You do not want to be stuck in the back- bags do not replace seat belts. country only to find that you are lacking the proper equipment or that the equipment you do have is not Make sure all your equipment is secured in the veworking. hicle. Murphy’s Law of driving says that any loose objects will end up under the brake pedal! Also, in a Inspect your vehicle before every trip. Another good worst-case scenario, loose objects become missiles practice, which most people neglect, is the post-trip inside the passenger area. TheDrivingCompany.com
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DYNAMIC RECOVERY ROPES AND STRAPS
Dynamic ropes or straps, often called “snatch ropes” or “straps,” are made of nylon or other material that stretches. Ropes stretch anywhere from 28–35%, and straps stretch from 18–22% depending on the manufacturer. This allows kinetic energy to be stored and released during a recovery operation. Because of the stored energy, do not use a chain as an extension. If a break occurs, the chain can be flung by the rope or strap with tremendous force. Never hook to a tow ball. These are not designed to handle the shearing force so if it breaks, the ball will become a high-speed projectile. Also, do not push the loop end of the rope into the hitch receiver and put a hitch pin through the loop. These pins are not designed for that use so they can fail. The pin may also bend, preventing removal. You can also cut your strap on the sharp edges of the receiver.
or agree on two horn honks for go and one horn honk for stop. The important thing is to not run over the rope or collide with each other once the stuck vehicle is free. The mobile vehicle is in 4WD low-range, 1st gear. The mobile vehicle accelerates in a smooth and controlled, but assertive manner. When the rope tightens, it will stretch. This stores and releases energy, which increases the effective pulling force the mobile vehicle would otherwise be able to generate with a static pull. The stuck vehicle should be in gear, ready to assist with slight throttle while being careful not to generate too much wheel spin that could worsen the problem.
Multiple attempts may be required. When using recovery straps, you will be limited to four attempts because the strap will need to rest for 48 hours before using it again as it needs time to regain its stretch characteristics. Dynamic ropes do not have When performing a dynamic recovery, or snatch, be this issue, but heat can build up internally during a sure the vehicles involved are directly in line with pull so wait one to two minutes between snatches. each other or within 10 degrees of in-line because once the rope becomes taught, the vehicles will be If the vehicles involved in the recovery are of differforced in line. If the vehicles are at an angle, a roll- ent sizes, then match the rope or strap weight rating over can result when they are forced in line, causing to the smaller vehicle. Matching to the larger vehicle one to slide sideways. will limit the amount of stretch that occurs, which could result in damage to the smaller vehicle. Check When connecting to the vehicles, connect to hooks with the vendor to match the correct rope or strap or tow hitches that are attached the vehicle’s frame. for your vehicle. Attaching to bumpers or suspension parts can cause serious vehicle damage. Some recovery hooks on Keep everyone well clear of the recovery operation. modern SUVs are not made for serious recovery ef- If anything breaks, it can fly at high speed causing forts. Make sure you know what the hooks are made serious injury or death. Place a dampener over the of and how they are attached to the frame before rope or strap so if it breaks, the dampener will slow you use them. it down. These dampeners will be torn to pieces in the event of a catastrophic failure so do not rely on A typical snatch involves safely connecting the rope these to stop anything. Keep well clear of the operto rated connection points on each vehicle. Have ation, and behind some kind of barrier. Once straps three to six feet of slack in the rope. The driver of or ropes are hooked up, never step over it even if it the mobile vehicle and the driver of the stuck vehicle is not under tension. need to have a plan on where to stop once the stuck vehicle is free. You can use radio communication TheDrivingCompany.com
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RECOVERY STRAP SAFETY Straps can easily be damaged, which will significantly compromise safety. Examples of damage include the following:
PUSHING
If you are going to manually push a vehicle to try and get it going, then there are things you need to consider. How many people do you have to push? Make sure everyone is wearing gloves. Make sure everyone knows what they are supposed to do and where they are supposed to grab the vehicle. Make sure there is a driver behind the wheel. Make sure everyone knows where the vehicle is supposed to go when it comes out. Be aware that debris may fly out from spinning wheels. Objects placed under the wheels can shoot out with amazing force. TheDrivingCompany.com
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WINCH OPERATION
This section will provide a summary of safe winch operation covering the basics to keep you as safe as possible when performing a winching recovery. For greater detail, you should attend a hands-on course or pick up a more comprehensive book on winching and recoveries. WINCH LINE
There are two types of winch line: steel and synthetic. Because synthetic line is susceptible to heat damage, it should not be used by agencies that operate in environments where the line is exposed to excessive heat. Even though you may not be doing a recovery over hot or recently burned ground, synthetic line can be damaged on the spool if an ember lands on it. Synthetic line is much easier to work with, so it is ideal for search and rescue personnel, and for recreational users. You can opt for synthetic or steel when purchasing a winch from many manufacturers. If you are replacing a line, check with the vendor to determine which line is best for your winch and your application.
The type of winch line you install on your winch depends on your winch rating and the weight of your vehicle. How much line you have on the spool also depends on your particular winch and the diameter of your line. You should install a winch line that has a breaking strength that is 1.5–2x the pulling capacity of the winch. For example, a 12,000 lb. winch Be sure to keep your winch line clean. With synthetic should have line on it that has a breaking strength of line, dirt and sand can act as sandpaper on the fibers 18,000–24,000 lb. when the line is flexed and moved. You also need to inspect the line for any damage as this can significantly reduce the strength of the line. TheDrivingCompany.com
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Winch Line Safety
Wear protective equipment such as safety glasses, gloves, and closed shoes or boots. Steel line has enough elasticity to create an extreme hazard if the line breaks. Dampeners should be placed on the line and everyone involved in the recovery operation should be in a safe position. The winch operator should put the hood up and operate the winch from inside the vehicle. Some people think there is no danger when a synthetic line breaks because it has negligible stretch. It is much safer than steel line but you should still use dampeners and keep people clear of the recovery operation. Do not let the line slip through your gloved hand when returning it to the spool. If there are any wires sticking out of a steel line, then they will go through your glove and into your hand. Synthetic line can pick up stickers or cactus needles that can also go through your glove. Do not handle the winch line near the fairlead when the winch controller is plugged in. If you need to adjust the line or hook it to something for storage, then unplug the winch first. You can plug it back in to take up the slack. If your hook or link sits flush to the fairlead, then take precautions such as using the small strap that comes with many winch lines for the purpose of keeping your hands clear of danger.
Safety Box
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The winch operator should establish a safety zone around the winch. This can be done by drawing lines on the ground with your foot around the front of your vehicle (or wherever the winch is mounted) that is large enough that if you stay out of the box you cannot reach the fairlead. One of the common injuries that occur when operating a winch is getting fingers caught in the fairlead. The only time you should handle the hook or loop guard near the fairlead or brush guard is when you are taking it out for use or putting it away after use.
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Double Check Verbal Contract
The winch operator and the riggers need to have clear and concise communication during a winching operation. You do not want to have the winch start winding in line when someone is still hooking things up or if they are standing in a potentially dangerous area. One effective way to get the riggers and the winch operator on the same page is to have a double-check verbal contract. Here is an example: Winch operator: “Ready to winch?” Rigger: “Ready.” Winch operator: “Winching.” Rigger: “Winch on.” The wording does not need to be exact, but the winch operator should be double-checking with the rigger to avoid miscommunication. In addition, any time the winch operator plugs the controller into the winch he or she announces, “Winch is hot.” The rigger will repeat, “Winch is hot.” This ensures that everyone knows the winch may inadvertently starting winding in line. Do not plug the controller in until the rigger is done hooking things up.
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Pulling Force
Using the Chart
Example scenario: A vehicle with a Gross Vehicle Weight Rating (GVWR) of 6,000 lb. is mired to wheel-depth (meaning over the bottom of the rim and any part of the axle or differential but not up to the frame or body) and it needs to be pulled up a 15 degree inYou will only get the maximum pull out of cline to recover it. (You can find the GVWR your winch when there is a single layer of of your vehicle on a placard inside the drivline on the spool. The pulling force will de- er’s door.) crease a significant amount with each layer that is added on the spool. For example, on To determine how much pull force you will a Warn 9,500 lb. winch you will lose rough- need, go to page 1 of the chart. At the “Start ly 1,000 lb. of pulling force for each layer Here” box, you will answer “Yes” to the added to the spool. The amount of pulling question, “Is it mired?” Follow the “Wheel force decrease is even greater with larger Depth” arrow to the right. You will see that winches. Check the owner’s manual for your the Mired Resistance is 2x the GVWR. Because our vehicle weight is 6,000 lb. in this winch for specifics. example, 2x 6,000 lb. is 12,000 lb. Now Calculating Required Pulling move to page 2 of the Flow Chart. Start with the Gross Vehicle Weight, not the number Force When performing a recovery using a winch, you came up with from page 1. In our exbeing able to estimate how much pulling ample, our vehicle weighs 6,000 lb. Follow force is necessary to keep within the rating the arrow that says, “15 degree incline.” This of your winch and within the ratings of your arrow leads to a box that reads, GVWR x associated gear (snatch blocks, shackles, 25%. Because our vehicle weighs 6,000 lb., etc.). The following flowchart is based on we multiply that by 25% and get 1,500 lb. US, Canadian, and UK military manuals and Add this number to the number we got from provides a general indication of the amount page 1 of 12,000 lb. and we get 13,500 lb. of pull force required. It is not intended to provide an exact mathematical calculation of Page 1: 12,000 lb. + Page 2: 1,500 lb. = the specific pull force required for a given 13,500 lb. of pulling force needed to recover situation. You may see other types of charts the vehicle in this scenario. This is an estithat provide different formulae, but they mate. add a certain percentage of error margin in the last step. We use the military formulae These formulae are used as guidance and that have these error margins built in be- give you a good margin of error. Every sitcause they give the largest margin of safety uation is different so there is never a way to as compared with other formulae we have calculate the exact amount of pulling force needed. Once you hook up the rigging, keep seen. a close eye on your connection points, your anchor, and your winch performance. Because each winch is different, refer to the owner’s manual for your particular winch. The important thing to know is the rating of your winch and how much pulling force is going to be required in any given situation.
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MECHANICAL ADVANTAGE Examples
It is possible to add more pulleys, which will increase your pulling force. The following section on calculating pulling and anchor forces will show how you can quickly overwhelm your rigging and exceed the tolerances of various pieces of equipment such as hitches, winch lines, snatch blocks, and shackles. Mechanical Advantage
This section will give you an overview of how to achieve mechanical advantage when setting up a winching operation. A pulley is essentially a moving lever. When you run a winch line through a pulley bringing it back 180 degrees to an anchor, you will achieve a 2:1 mechanical advantage. Mechanical advantage is achieved whether the winch is moving toward the pulley or the pulley is moving toward the winch. As you diminish the angle, you diminish the mechanical advantage. Once you are at 90 degrees you gain no mechanical advantage, you merely have a change of direction for your winch line. The physics behind this are beyond the scope of this text but there are plenty of sizable books on this subject if you are curious about the details. Discussed here are the critical aspects of calculating the pulling forces and the anchor forces involved. This will allow you to rig your recovery in a safe manner.
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MECHANICAL ADVANTAGE
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Screw Pin Shackle
These are also known as “Screw Pin Clevis,” “Bow Shackles,” “D-Shackles,” and a few other names, and come in various sizes and weight ratings. You can purchase these from reputable manufacturers in the US, Canada, or the Netherlands. Warn Industries also sells quality, tested gear. These companies put their gear through stress testing and they possess ductility; i.e., they will deform before failure rather than shatter in catastrophic fashion. Screw Pin Shackles made in China are not tested in the same manner and tested in the same manner and they do not possess ductility. The Driving Company will not use shackles made in China. Screw Pin Shackle ratings are stamped on them. “WLL” stands for Working Load Limit. This is usually followed by a number, such as 6½ t. This is the Working Load Limit for hoisting or vertical lifting. A lower case “t” is for metric tons (2,204 lb.) and an upper case “T” is for US tons (2,000 lb.). The number 6 is stamped on the Screw Pin Shackle pictured below. This is used to determine the Maximum Breaking Load (MBL) for this particular type of shackle. To find the MBL, multiply the WLL by this number. For a WLL of 6½ t (14,326 lb.) with a multiplier of 6, we get a rating of 85,956 lb. The MBL of a Screw Pin Shackle with a WLL of 6½ metric tons and a safety rating of 6 is 85,956 lb. The Driving Company recommends keeping your load on the Screw Pin Shackle to ½ the MBL or less. In this example, we would not want to pull more than 42,978 lb. The ratings are only when you are pulling in a straight line from front to back on the shackle. The rating will decrease significantly as sideloading increases. Use the pin that comes with the shackle as it is rated. Do not mix screw pins and do not use a bolt or cotter pin. Make sure you are using only Screw Pin Shackles, not Bolt-Type Shackles. Many people will tighten the pin, and then back it off a quarter-turn when doing a pull. The shackle will flex, so you do not want to back the pin off. It should be fully seated such that the shackle keeps its designed shape under stress. If you are doing a hard pull, then tighten the pin 1/8 turn more with a small wrench.
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Snatch Blocks Snatch Blocks or pulleys are used to create mechanical advantage or to change the direction of a winch line. Be sure that the snatch block rating is at least 2x the rating of the winch. If you are doing a 2-line pull, then you can potentially double the force of the winch so it is critical that the snatch block can handle this load.
soft shackles
Soft Shackles
Soft shackles are made of synthetic rope, making them much lighter and easier to work with than steel shackles. They will have ratings ranging from 16,000 to 125,000 lb. They will float in water and you can lay them on snow without them sinking. These can be wrapped around rated recovery points on a vehicle as long as there are no sharp edges because soft shackles can be cut. Check with the vendor to determine which soft shackles will meet your needs based on your vehicle weight and winch rating. Purchase these from established, reputable companies. They can be expensive, but you get what you pay for. There are some Soft Shackles on the market that are cheaper, but they are not tested in a con-
trolled setting.
Soft shackles are much easier to use than Screw Pin Shackles, but they are also susceptible to damage. Like synthetic winch line, heat can damage them and they can be cut if they come into contact with sharp edges under load.
Deploying a Snatch Block even if the winch can handle the job with a 1-line pull can be beneficial. Less stress is put on the winch and there is less stress on the electrical system of the vehicle. There will be reduced winching speed but the stress on the winch is less. The winching rate will naturally slow down when the winch is pulling hard anyway. “Slow and steady” in a winching operation is good, so slowing of the recovery rate is not a bad thing. There are many types of snatch blocks. Be sure the snatch block you have will accommodate the winch line diameter. The size of the sheave, or wheel is also important. To determine the proper size sheave, use a 12:1 ratio. A 3/8” winch line multiplied by 12 means a 4.5” is a good diameter for your line. Synthetic line is more flexible so you can go as low as a 6:1 ratio for a 3/8” synthetic line. This would be a 2.25” sheave. Do not run synthetic winch line through a snatch block that has been used with steel line. The steel line will roughen the pully wheel, making the wheel abrasive enough to damage synthetic line.
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Hitch Link
A Hitch Link fits in the sleeve of the trailer hitch, allowing connection of a Screw Pin Shackle or Soft Shackle. When using Soft Shackles, be sure to use a Hitch Link that has smooth edges. Some have sharper edges that can cut or damage Soft Shackles. When using a Hitch Link, be sure you know the rating of the trailer hitch.
Never use a tow ball as a connection point for a static or dynamic recovery. The tow ball is not designed to withstand that amount of shearing force. If the ball breaks, it can be flung with lethal force. The Hitch Link is secured in the hitch with a pin. Make sure you use a rated pin designed for this particular use. Do not use a bolt!
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Chain:
Chain can be helpful for things like extending the winch line but be sure you are using rated chain. Like other recovery gear, chains have ratings. Too many people go to the hardware store, buy a length of cheap chain off a roll, and then put unrated hooks on it. Make sure you get rated, made in the USA chain from a reputable company. The rating or grade of chain is marked on the chain every few links. Grade 70, 80, or 100 is recommended for off-road use in the sizes below. As with the Screw Pin Shackle, the Working Load Limit (WLL) is for hoisting. The MBL multiplier is 4 for chain of these grades.
3/8 inch Grade 70 Chain: WLL 6,600 lb. x 4 = 26,400 lb. MBL 3/8 inch Grade 80 Chain: WLL 7,100 lb. x 4 = 28,400 lb. MBL 3/8 inch Grade 100 Chain: WLL 8,800 lb. x 4 = 35,200 lb. MBL The hooks on each end should be the same grade as the chain or higher. Like the Screw Pin Shackle, keep the pull force on the chain to ½ or less of the MBL.
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Recovery Gear Suggestions
Now that you know about available recovery gear, what should you actually carry with you? The Driving Company is not sponsored by any manufacturer or vendor. We make a few specific recommendations based on the quality and performance of the products, not because a vendor or manufacturer sponsors us.
Winch Lines Synthetic Winch Line: For Search & Rescue personnel, recreational use, and for some Fire Department applications (if the line can be protected from embers and hot surfaces). Pros – easier to work with, lighter, stronger, safer in the event of a failure. Cons – can be damaged by heat (embers), more susceptible to cutting damage, can be damaged by UV light over time.
Type III Rigs If you are using this hardware on the front bumper of a Type III with a single triangular-shaped anchor plate connected to both frame rails (commonly found on CalFire and OES vehicles), then a 1-1/8 Screw Pin Shackle is required to prevent pinching the eye of a 1.5 inch Kinetic Rope.
Two 1-1/8 inch Screw Pin Shackles for triangular-shaped Steel Winch Line: For Fire Department personnel and anchor plate recreational use. Pros - Not as susceptible to heat and Four 7/8 inch Screw Pin Shackles ember damage. Cons – very dangerous in the event of Six ¾ inch Screw Pin Shackles failure, heavier, difficult to work with, difficult to spool. Snatch Block: Suggested Rating: 1.5–2x the winch rating. Because you are creating mechanical advantage with a Example: a 9.5k lb. winch would require 5/16 inch pulley, you will need a Snatch Block rated at least 2x the (16,500 lb.) and length of 100 feet, or 3/8 inch (21,700 winch rating with a safety margin. Be sure to purchase lb.) and length of 85 feet. a reputable brand. If you will be on the trail by yourself, then we suggest having two. Master Pull, ARB, and Thicker line will take up more space so the length you Warn all have quality, tested pulleys. Snatch Blocks reccan get on the spool is less. Some types of synthetic line ommended by the winch manufacturer, such as Warn, are open-weave while others have a sheath that protects have a built-in safety margin. the line from sand, mud, and dirt. Open-weave requires more attention to keep clean to avoid long-term damage. Type III and Type VI Rigs Sheathed lines cannot be spliced easily on the trail if they Master Pull Snatch Block SB75000-22 rated for get damaged. 75,000 lb. Warn Epic Snatch Block PN #93195 for winches rated Winch Line Extension: Be sure to get a line to18,000 lb. that is rated for at least 2x the rating of your winch plus a Recommend having a minimum of two Snatch Blocks, safety factor of 1.5. For example, a winch rated at 12,000 but three is preferred. lb. would get a winch line rated at 36,000 lb. or more (12,000 x 2= 24,000. 24,000 x 1.5 = 36,000). This way, Kinetic Rope / Snatch Strap: you can use a 2:1 mechanical advantage to the exten- We recommend Master Pull Super Yanker, or Bubba sion and only have to use one extension from the snatch Rope. The Bubba Rope is more expensive but we really block to the anchor point. You can get synthetic line for like the Gatorizing. It helps keep foxtails and mud out the extension. It is easy to store, lightweight, and easy to of the rope. The only drawback with the Bubba Rope is carry and work with. Although it is susceptible to heat that it is not as flexible as the Super Yanker so it requires damage, you would probably not have time to set up a more room for storage. If storage space is tight, then the recovery that requires an extension in an active fire situ- Super Yanker is better for you. ation anyway. Jeeps, SUVs, and pickups under 10,000 lb. GVWR Gear Bag: You can spend a lot of money for gear One 7/8 or 1 inch x 30 feet rope. These have a 30–35% bags or go to Home stretch and are rated for 28,500 lb. for the 7/8 inch or Depot and get Husky tool storage bags. Amazon and 33,500 lb. for the 1 inch rope. Lowe’s also sell them. We prefer the ropes, but if you would like a strap, then Screw Pin Shackles: We recommend Van we recommend the ARB 30 foot with a 24,000 or 33,000 Beest or Crosby. The Van Beest is top quality and close lb. rating. ARB guarantees 20% stretch. Keep in mind to 1/2 the price of Crosby. that the snatch straps should only be used for four sequential hard pulls. After the fourth sequential pull, they Jeeps, SUVs, and pickups under 10,000 lb. GVWR need to rest for 48 hours. Six 3/4 inch Screw Pin Shackles One 7/8 inch Screw Pin Shackle Type VI Vehicles over 10,000 lb. GVWR One 1.25 inch x 30 feet rated at 52,000 lb. Type VI Rigs over 10,000 lb. GVWR Two 7/8 inch Screw Pin Shackles Type III Rigs Four 3/4 inch Screw Pin Shackles One 1.5 inch x 30 feet rated at 74,000 lb. TheDrivingCompany.com
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Tow Strap: Bubba Rope has an excellent 20-foot tow strap rated at 23,500 lb. You really don’t want your expensive Kinetic Rope dragging on the ground or getting run over by the person that is being towed. Tree Savers / Bridle: We recommend having two 3 inch x 10 feet tree savers from Master Pull rated at 54,000 lb. This will allow you to use them as tree savers, winch line extensions, or as a bridle. To fashion a bridal, hook one strap to each of your front tow hooks and then connect the ends together with a Soft Shackle or Screw Pin Shackle. You can then connect your winch line. If you are connecting a bridal to a Kinetic Rope, then use a Soft Shackle. Do not use a Screw Pin Shackle, because if something breaks, you do not want to have a steel shackle attached to the end of a giant sling shot.
Traction Boards: There are several companies that sell traction boards. We recommend Maxtrax. They are expensive, but you get what you pay for in terms of quality. Traction boards take up a lot of room to store but they can really make life easier. We recommend getting four boards if you decide to purchase them. The extreme model has anodized alloy teeth that are replaceable. You must be extremely careful not to spin your wheels on these boards because it may cause tire damage. Follow the manufacturer’s instructions and recommendations.
Portable Air Compressor: Be sure to purchase a top-quality air compressor. Get one that has a regulated automatic pressure cut-off. If it shuts itself off automatically, then you won’t have to switch it off every time you stop inflating a tire. Pay special attention to the duty cycle and CFM output. If it plugs into a Chain: power-port socket, then it is a light-duty compressor. Get Be sure to get “Made in the USA” chain because it is rat- one that clips directly onto the battery. We have had good ed and tested. These can be purchased from cargo trans- luck with Viair and we recommend 4500 HP or higher. port suppliers, rigging companies, and logging companies. We highly recommend keeping a spare inflator chuck and These are heavy so shipping can be expensive. air hose on hand. It is very easy to burn or cut the hose. It is also easy to lose the inflator chuck in deep snow, sand, Jeeps, SUVs, and pickups or mud. 3/8 inch, grade 70 transport chain with Clevis Grab Hooks on each end. A 12-foot length will work for most High-Lift Jack applications. There are many opinions on this tool. It can be used for jacking a vehicle up when stuck, or it can used as a comeType III and Type VI Rigs along. The Driving Company has been training people 3/8 inch, grade 100 chain with Clevis Grab Hooks on since 2003. We have found that this tool can be very daneach end. A 20-foot length will work for most applica- gerous if you are not proficient with it. Most people do tions. not have the need to use it very often, so on the rare occasion they break it out they are unfamiliar with it. We call Hitch Link: this a high-risk, low-frequency activity. In our opinion, This fits into your 2 inch hitch receiver for an anchor the risk-to-benefit ratio for these is not worth it unless point. you practice with it. We understand others disagree and Warn or Factor 55 have quality, tested Hitch Links. Fac- they love this tool. We agree it can be a useful tool but tor 55 is lighter and has smooth edges, making it easier on only if you stay proficient and practice with it. If you add your Soft Shackles. this to your equipment inventory, then practice with it and maintain all moving parts on a regular basis. Soft Shackles: We recommend Bubba Rope Gator Jaws. The Bubba Tire Patch Kit Rope Gator Jaws exceeded the stated strength ratings Carry a basic tire patch kit that has plugs, glue, and tools. during destructive testing. These product names can We recommend the T-handle tools because they are much change so look for ratings that are at or above our rec- easier to use than the straight handle. Also, carry a sepaommendations. rate sidewall patch kit. Jeeps, SUVs, and pickups Four 3/8 inch Gator Jaws rated at 47,000 lb. Type VI Rigs Four Gator Jaws rated at 52,300 or 76,000 lb.
Basic Tool Kit Carry a basic tool kit with screw drivers, wrenches, and the like for making minor repairs.
Two-Way Radios FMRS, GMRS, or CB radios are very useful when on Type III Rigs the trail with others in order to keep together. The lead Four Gator Jaws rated at 125,000 lb. vehicle can warn others of upcoming hazards. And, of course, you can tease each other over the radio! The DrivShovel: ing Company prefers GMRS but check with the FCC for Full-sized shovels are good for getting under the vehicle any required license. without laying in mud, snow, and muck. For snow and sand, I have found the square point to be most effective in making tire ramps. The round point is much better for digging, especially when digging a dead-man anchor into dry soil. I suggest having a 5 lb. Pick Mattock to complement your shovel. TheDrivingCompany.com
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Defensive Driving Your SUV, pickup, or Jeep is not a car. It does not perform like a car; that is, it has different handling characteristics than a car and a higher center of gravity. Don’t try to drive it like a car! Your stopping distance is generally greater than that of a car so give yourself more room for braking. Your following distance from the vehicle in front of you should be three seconds. If you are inside the three-second margin, then you should be paying very close attention to not only the vehicle in front of you but also to what is ahead of the vehicle in front of you. That means no talking on your cell phone, no eating lunch, no reading maps. If you are inside the three-second margin, then you better have a plan other than just slamming on the brakes. If you are inside 1.5 seconds, then I hope you are heavily insured because only luck will save you from getting into an accident.
Weight Transfer Side-to-side, or lateral weight transfer is responsible for many rollover accidents. When making a quick turning movement to avoid an accident, most people put in too much steering and then try to correct by turning too much back in the other direction. This starts an oscillation that can lead to a rollover after just two and one-half turns. The more steering you put in the more weight transfer you will have and the more steering you will eventually have to take out.
Your focal point, i.e., where you are looking, is in great part what determines where your vehicle is going to go. It will go where you look whether you want it to or not. If you look at a hazard you will probably hit it. If a hazard presents itself, then look to an escape route and drive there. This is called “driving to the solution.”
You can use the same concept to correct for oversteer. Most of us were taught to turn in the direction of the skid during an oversteer (where the rear end slides or fishtails to the outside of a turn). Instead, look where you want to go and open your hands releasing your grip on the wheel. The caster effect will take over and the steering wheel will turn itself in the direction of the skid. It will turn exactly how much it needs to turn and as fast as it needs to turn. If you do not try and help it, then it will come back to center and you will have little or no secondary skid. If you are in an extremely low-traction situation such as ice, then the caster effect may be too weak to help you. In this case, you would steer in the direction of the slide. Be careful not to input too much steering because that will cause a secondary slide once it recovers.
To correct lateral weight transfer problems, allow the vehicle to center itself by releasing your grip on the steering wheel and allowing the vehicle to center itself. Do not take your hands away from the wheel: ease your grip allowing the wheel to center on its own. This is called the “caster effect.” The front wheels are casters and they want to go straight if you only let them. Remember to look where you Drive the speed limit. Speed limits are put in place want to go and then let the vehicle correct itself by for a reason. allowing the steering wheel to center itself.
Driving within the law and your talent level, coupled with the knowledge of stopping distances and how focal points work, will keep you out of many bad road situations. You cannot control the actions of other drivers, but if you are paying attention you can recognize the mistakes they are making and stay clear of them.
The Environment It is important that you observe environmentally friendly driving habits. You can set an example that others will follow. The following are some tips for environmentally friendly driving. For more information on environmentally friendly off-road driving, visit Tread Lightly!
* Use existing campsites. Camp at least 200 feet from water to avoid contaminating lakes and streams. * If you encounter travelers on horseback, turn off your vehicle and wait for them to pass.
* Be considerate of others who are enjoying the backcountry. Not everyone travels by vehicle. Respect the * Cross streams only at established fording points. camping areas of others. If leaving or arriving at odd Small creatures live in the stream and can be run over hours, then show some manners and keep the noise down! if you cross at other than established spots. * Driving up and down stream can also disturb fish * Take only pictures and leave only (minimal) tire tracks. and other wildlife: don’t do it! * Avoid unnecessary wheel-spin, which can damage * If you pack it in, pack it out. Do not litter! When practical, pick up trash left by others as an example the terrain. to all. * Do not stray from the established trail or road. Blazing your own trail is unnecessary and damages * Wash your vehicle after each trip off-road. This prevents transporting seeds from non-native plants vegetation and habitat. and weeds from one area to another. TheDrivingCompany.com
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ABOUT THE INSTRUCTOR
DAVE STORTON
Dave Storton holds a Master’s Degree in Adult Education and has been teaching since 1993. He is recognized by the State of California (POST) as an expert in vehicle operations and off road training. He is a lead instructor for the emergency vehicle operations course (EVOC) at South Bay Regional Academy. Dave teaches EVOC instructor courses, advanced EVOC instructor courses, off road EVOC, and counter-terrorist / dignitary protection driving. In addition to instructing civilian off road courses and leading off road adventures, he teaches Hollywood stunt drivers at Bobby Ore’s Motion Picture Stunt Driving School. He also teaches leadership / team-building, and he teaches other instructors the art of facilitation and adult learning concepts in a POST certified Instructor Development Course. After 30 years in law enforcement, Dave retired in 2012, which has allowed him to devote his time to teaching. Dave has been featured for his driving expertise on Mythbusters, Fox News Channel’s Fox Report with Sheppard Smith, The Discovery Channel, the New York Times, the San Jose Mercury News, and the Monterey Hearld. Special thank you to Instructor Ron Waterman for his extensive expertise and input in creating this workbook
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Email: TheDrivingCompany@gmail.com Phone Number: (831) 245-3377
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