*BOV off road driving, recovery and expedient repair tips, Pt. 1*
As prepared survivalists, we've all got 4x4's, winches front and rear on them, upgraded suspensions, reliability modifications, etc. Right? What? There's a chorus out there saying "no, we don't"?
Well, this article is for everyone with a BOV - whether it's a M35A2 Duece and a Half, or a Ford Focus. It'll primarily deal with self recovery, but there are a few tips in it for those who'll have some other vehicles along too.
Know Thy Tools
First off, know your vehicle. Know where the wheels are, have a feel for how much ground clearance you have, and what the breakover angles are (breakover angle basically means the highest bump you can go over without losing traction and high centering the vehicle). Become familiar enough with the controls that you don't have to look at them to use them - shift levers and parking brakes especially. Know what's underneath the vehicle - what the soft spots are, such as oil pans (engine and tranny), fuel tanks, etc. Most of us already have accelerator, brake, and clutch control down. I hope. If not, work on it - the vehicle should be part of you, and you should be able to control it reflexively.
How To Gettest Thy Conveyance Stuck
Getting stuck can happen in the darnedest places - places you'd never think will be a problem, can become problems. Something as easy as trying to cross a small dry or wet depression can become very hard, if you don't have traction, or know your approach and departure angles. (approach and departure angles, respectively, are the front and rear angles created by the forward (or rear)/lowest hard point and the point of front contact of the tire. Basically, it's the angle you can go into a slope without digging in your front or rear)
For any vehicle, the best way to learn what it can do is to do it. Get out there and facta non verba it. Learn how your vehicle works on hard pack, sand, mud, grassy slopes, ditches, etc. Take it easy, and get out a lot when you're doing this to see what's happening. Be aware that you might not be as heavily loaded as you will be during a bug out, and that can have a huge effect - sometimes for the better, sometimes for the worse. Each vehicle will have different characteristics.
Terrain to be cautious about can be the usual mud and sand - but have you thought that the shoulder you're thinking of driving on might just have been hit by irrigation sprinklers, and what looks dry is actually a foot of saturated ground?
Which brings us to our first rule of BOV off roading: If you can, get out and look at the area you want to cross. Walk it, probe it, assess it.
Now, if you're in a hurry, as might well happen in a BOV situation, use the second rule: Momentum is our friend. Please use this within reason, and practice it. Oftentimes, the best way to get across questionable areas is with momentum and speed. You've got to balance this with the breakage possibility though - again, know your vehicle.
If you're going to be traversing lots of off road terrain, and know you're going to be getting into the soft stuff, or crossing rocks, ditches, etc., learn how to "air down". All this means is letting some of the air out of the tire, dropping the pressure, and getting better traction and floatation. Just as a guideline, on off road tires it's common to air down to 2/3 to 1/2, or less, of their rated pressure. So on my 10,000 pound maintenance truck with 37x12.5 radials (sidewall pressure rated at 40 psi, I'll air down to 20 pounds to begin with...and then go from there. However, each tire/vehicle/load situatin is different, so experiment. If you roll your tires off the rim while you're experimenting, you're doing it right, and learning what you need to. Which will lead us to a later point in this article on how to re-mount tires in the field. The primary hazards when you're aired down are the tire coming off the rim due to turning too hard, and overheating if you're driving too fast, both of which will stop you quickly. So - air down when off road, and re-inflate to proper pressures (and that doesn't necessarily mean what's on the tire sidewall either) once you're back on the road. Also realize that heavy loads will affect how much you can air down. Keep those off road speeds low if you're going over rough terrain too. And, of course, have some way to air back up once you need to.
Thou Art Stuck
OK, so you walked it, it looked good, but you got stuck anyway. Or that momentum just carried you into a more serious mire - hey, it happens to the best of us.
With any vehicle, 4x4, 6x6, or 4x2 - as soon as forward motion is completely stopped, get off that accelerator! If you stay on the power, all you're going to do is dig those tires in deeper, and make it harder to dig yourself out.(If you've driven enough, and have a good feel for the vehicle, one other alternative is to immediately shift into reverse - as the vehicle slows its forward motion, there'll be a small rebound to the rear. Sometimes you can use this rebound, and if you're fast enough and have the technique, you can drive out in reverse. Again, something to practice)
Once you're stopped, get out and assess the situation. What's holding you up? Soft ground, mud, sand, slope, ditch, rock? Are there any projections that can rip a hole in an essential part if you start moving again? Is there an easier avenue to get out of this hole, or was the original direction of travel a good choice? If I have it available, was I in four wheel drive? Were my hubs locked, if I've got manual hubs?
Thou Hast Chosen To Bog Thyself Down In Primordial Slime:
If you've bogged down in mud, and believe me, there are plenty of different types of mud, here are a few things you can try. Got a set of snow chains? Use them! Unload the vehicle to get it as light as possible. Rocking it back and forth will sometimes help get you out - by rocking it, I mean shifting between forward and reverse, trying to build up momentum in either direction, at which point you can drive on. Apply power, and turn the front wheels alternately left and right...go full lock to lock if you have to, and keep the power on. (This is only for front wheel drive vehicles, and four wheel drives though - doesn't help with rear wheel drives). If none of these things are working, and you'll know within seconds if they will or won't, look around for anything that'll give grip - rocks, branches, chain link fence, old wood, carpeting from the car or truck, seats taken out, etc. Take your shovel (you've got one, right?) and scoop out some of the muck from around the tires, and shove that filler under/behind/in front of the tires. You're looking to make more or less of a ramp to go up, but with a better surface than the surrounding muck. This goes for both driven and non-driven wheels. If you've got a hi-lift, ranchers, or similiar jack, try jacking up the corners of the vehicle and getting the tires above the surface. Fill the hole that the tire was in with debris, and move on to the next stuck tire. Once that's done, find your tire valves, clean them off, uncap them (you do have caps on them, right?) , and start airing down. By airing down (letting the pressure get lower in the tire) you'll increase the surface area and "give" of the tire, letting it conform to the terrain better, and often letting the tire lugs or traction surfaces get more bite. (That being said, for some mud conditions, it's best not to air down, but to keep the pressure high. This is primarily if you have a solid surface underneath the soft stuff - but if that's the case, usually you'll have been able to drive out to begin with. It's something to check out though...) If you've got passengers, use them as they were intended to be used - tell them to push. At the least, get them out to lessen the load. Sometimes all it takes is just a few extra pounds of force to get you out, and a couple of people pushing will do it.
Important points:Use traction aids, turn wheels side to side while powering out, stop when no forward motion is happening, start jacking/digging/filling - know where you're going to go next.
Thou Hast Opted For The Sand Stuckness Option:
Before you go anywhere that's dry and sandy, air down, air down, air down. Then air down some more. In general, this will prevent 90% of the mires that'll happen. If you didn't air down, as soon as you feel the forward momentum stop, get off that accelerator. Get out, and air down. Look and walk the terrain where you want to go - is it more of the same? If so, you might want to reconsider your line of travel. This might be a good time to back out and take another route - oftentimes only a few feet to one side or the other can be the difference between making it through, or practicing extrication techniques. Once you've dropped the tire pressure, oftentimes you can just get back in and drive out. If you're still concerned that you can't, or you can't air down due to the load, then take that shovel and get the sand out of the way of the tire - make ramps for the tire to go up, and make them long. If you've got scraps of carpet, chain link fence, wood, etc, now is the time to line that ramp. Usually I'll make ramps to the rear of the tires too - this'll be used to first back up a bit, and then roll forward, using the momentum to help get out. Don't skimp on making the ramps - take your time, and make them long. It's not unusual for me to make the ramp for the rear tire four feet long, and same for the front. If you've got a manual transmission, a trick is to use a higher gear, with the idea being to lessen the torque so you don't have as high a chance of getting digging in. Yet another trick is to ride the emergency or parking brake slightly (this only works on vehicles that have rear brake drum parking or e-brakes. It won't work on driveline brakes, or front wheel drive vehicles). By riding the parking brake a little, you'l be effectively creating a "poor mans limited slip differential". Braking with the hand lever will force whichever wheel is freely spinning to slow down, forcing the other wheel with traction to do more work. It's a very effective technique, when done properly. As with all of this stuff....practice makes perfect. Once you're out of the mire, don't stop! Keep that momentum and speed up! Get to more solid ground (you've identified that by....all together now....."walking the terrain", right?) Then you can stop and re-load, air up, etc. If it's only a few feet away, great. If it's a half mile, so be it. In general though, since we don't have many extremely sandy areas, such as sand dunes to deal with, there'll be some area to stop within a reasonable distance. Sometimes you can look for vegetation that has stabilized the sand, and that'll be a good place to stop. Sometimes slightly damper sand will be good - but watch out for quicksands!
Air down, get off the gas when you're not moving, start digging, use momentum/speed to keep moving and know where you're going to go next.
Thou Hast Chosen To Have Fun With Wet Grassy Slopes:
Wet grass, or low, wet vegetation in general, is one of the most treacherous terrains to cross. The grass, moisture, and other plant matter all can combine to make something akin to oil on an ice rink. Even the best equipped rigs will often fail at making it up slopes with something like this, turning forward travel into a winching exercise. Think twice before traveling across this stuff, up slope, down slopes, and one of the worst possible ones, side slopes. If you do have to go up this sort of stuff, use snow chains if possible, and use momentum to get up it. It might take a few tries, or you might just have to go around. Playing with the e-brake technique, and wheelspin might help too. If it's on a sideslope, approach with caution - and if you're one of those folks that have lockers installed in the axles, I'd recommend not using them unless you have to - this goes for muddy tracks that are sidehills also. If you've got Detroits, or other full lockers in there, be careful with those side slopes. Limited slips are a bit easier to deal with. One last thing: if you do get stopped on a wet slope like this, do not, whatever you do, attempt to turn around. Just put the vehicle in reverse, and back down slowly. Try to keep the tires from breaking loose - if you need to get the speed up to prevent this, that's ok, but be careful.
Important points:Use traction aids, use momentum, be very careful on sideslopes.
Thou Hast Chosen To Make Merry With Ditch Crossings:
Ditches are a pain, and can be amazingly difficult to cross. If there's time, and it's a sizeable ditch, fill it, or dig ramps. Rocks, dirt, gravel, branches are all good to create crossable areas. When you're approaching a ditch, crack, or crevice that's impeding your forward travel, the first rule is to get out and look at it. Maybe there's a better place to cross a bit away? If not, approach the point you want to cross at an angle - what you want to do is drop only one wheel at a time into the ditch, and then slowly climb out, letting the next wheel drop in. Repeat until you're clear. This is one type of obstacle that usually doesn't need lessened vehicle weight - usually just the opposite, in that more weight will work better, giving more traction. If you're in a two wheel drive vehicle, and have some helpers, another thing to try (in addition to the e-brake trick, approaching diagonally, etc) is to put weight onto whatever tire is breaking loose - usually that'll be the wheel that's diagonally opposite the one that's in the ditch. One very fast and simple way to weight the wheel is to get a passenger, or two, to stand on the bumper closest to the wheel with lowest traction. Sometimes if they bounce it up and down, it helps. Be very careful with this technique though - it's all to easy to rev it up, and then when the tire catches, it launches the vehicle over the ditch, flipping the helpers off. If they're unlucky, it'll put them under a tire.....
Important points:low gear, go slow, approach on a diagonal, use weight aids.
Thou Hast Encountered Multiple Rocks, Yea, Verily Many
Rocky areas (babyheads, we call 'em around here) are always fun. Main thing here to remember is to go slowly. If there's a rock that you can't clear - or even if you're slightly uncertain it'll clear your undercarriage, put your tire right on it and drive over. Use your lowest gearing in these areas, and crawl right on over. Be aware of your approach/departure/breakover angles too. If there's a rock you have to go over, but it's too tall, steep, etc, pile smaller rocks to make a ramp. Be certain you know what's on the other side though. Often it helps to air down too.
Important points:low gear, go slow, air down, place tires on rocks instead of around them.
So to conclude this - always remember that if the area is questionable, and you've got the time, walk it first. If you start to lose forward momentum, it might be a good time to stop the power before you dig in. Know your vehicle. Know some quick and dirty aids for traction - snow chains, people weighting corners, more/less weight in vehicle, etc.
In part two, I'll deal with recovery techniques, both pre-planned like winches, and expedient, like using wheels as winches (I'll also deal with winch and rigging techniques). Part three will deal with emergency repair tips, and field repair tips.
Have fun with it - and if you have any questions, feel free to email or contact me on the boards.
All materials at this site not otherwise credited are Copyright © 1996 - 2005 Trip Williams. All rights reserved. May be reproduced for personal use only. Use of any material contained herein is subject to stated terms or written permission.