4WD training with a 2WD sedan

View fullsize

Anyone who has watched several four-wheel-drive vehicles in a row negotiate a difficult section of trail has noticed that some seem to do so with ease, while others struggle. Frequently this is due to differences in the vehicles—suspension, ground clearance, lockers, etc.—but sometimes, counterintuitively, a bone-stock model of no particularly superior breed will make light work of a passage through which a modified über machine struggled.

The difference, of course is the driver. And what that driver is doing is optimizing the capabilities of the vehicle by picking the proper line through, around, or over obstacles in his path.

That skill of being able to recognize the proper line will benefit you more than all the traction aids on earth. And just what is The Proper Line? In one sentence, it is: A course that will, as far as is possible, keep all four of the vehicle’s wheels in contact with the surface (for optimum traction), while keeping all parts of the vehicle’s bodywork away from that surface (for reduced damage), and maintaining the vehicle’s stability (to avoid rolls, plunges off cliffs, etc.). Okay, that’s a sentence fragment, but you get the point.

Bad line - tires in the low spots.

Even on easy trails, it’s worthwhile to train yourself to instinctively scan the terrain ahead and pick the optimum line. And some time ago I realized that the ideal vehicle for such training need not even be four-wheel-drive. The last two miles of the seven-mile dirt road to our little place in the desert has steadily degraded in the last few years, due to erosion from summer thunderstorms. As a result, the trip in and out is becoming more and more of a challenge for our old Mercedes 300D. Yet we’ve both been enjoying that challenge: easing it through ditches at just the right angle, straddling water-cut ravines that run straight down the road, judging the height of rocks on one bouldery downhill, and getting the speed just right on the final loose climb to the gate. You’re constantly reminded of axioms that serve well whether you’re working with five inches of ground clearance or twice that.

• Straddling a water cut going uphill is usually safe, since they get narrower as you go. Beware doing the same thing downhill, when the cut is picking up micro-flows from the sides and getting wider. You might find yourself caught straddling a ditch too deep to cut across, and have to back up.
• Precise wheel placement is a valuable skill. Know where your vehicle ends, and where each tire is going.
• Keep your tires on the high spots.
• Ditches perpendicular to the road are best crossed at an angle, one wheel at a time. Since the Merc has . . . modest . . . articulation and no traction aids, lifting a rear wheel is easy and will instantly cut traction. Sometimes a blip of the throttle is needed to coast across an air gap.
• Loose, steep uphills with two-wheel (i.e. one-wheel) drive are a balancing act between ensuring sufficient initial momentum while avoiding excessive, rock-spewing speed. The perfect choice results in topping out at a walking pace with nary a spin of a tire. 
• Closely spaced rocks can cause a feedback oscillation of the springs that cuts ground clearance drastically. Take them slow.
• Finally, learn the undercarriage of your vehicle, and where the delicate bits are. Most cars have one side or the other that would be easier to damage—good to know if you have to drive over a rock.

View fullsize

Fortunately the W123 series Mercedes Benzes were built like Panzers to begin with, and ours seems to be handling its backroad duties with aplomb. Still, we occasionally muse on maybe a two-inch lift, an ARB locker, and some All-Terrains . . .

Just say no to wheel spacers . . .

View fullsize

( . . . and other “performance enhancements” that compromise reliability)

Every once in a while—well, quite frequently, actually—my friend and master Toyota mechanic, Bill Lee, reads something in a magazine that sets his teeth on edge, and he’ll fire off an email to me sprinkled with a lot of exclamation points. Invariably the offending passage involves a “build” article, wherein the writer has taken a perfectly functional truck and set about “improving” it. I seem to be Bill’s favorite person with whom to share his pain, perhaps because I react the same way when I read some of this stuff, which, when published nationally, thousands of readers are likely to take as gospel and imitate.

It’s not that either of us is against any modifications at all. Many accessories can add to the utility, convenience, and even safety of a four-wheel-drive vehicle without compromising reliability or durability: better tires, driving lights, winches, bumpers with proper recovery points, dual-battery systems, built-in air compressors, etc. Even some driveline and chassis modifications can be made that have few or no drawbacks. Electric locking differentials, for example, generally do not compromise the strength of the third member, and if they stop working you’re normally just back to a stock diff. Aftermarket shock absorbers frequently exceed the performance of factory units—especially if, as in our case, you’ve added a 1,000-pound camper to your truck. High-quality aftermarket springs (or, in the rear, air bags) can enhance weight-carrying ability, or improve ride.

The problems start when you begin messing with the fundamental engineering and design parameters of the truck.

Bill’s most recent email concerned a Tacoma on which the writer had installed, among other things, new, wider tires. He subsequently found that the tires rubbed the inner fender wells at full steering lock, especially when the suspension was compressed. So, rethink and install narrower tires? Nope. Instead, he installed a set of 1.25-inch wheel spacers—an inexpensive, bolt-on accessory that literally moves each wheel outward from its hub by an inch and a quarter. This, the writer reported, (mostly) solved the rubbing issue, and additionally widened the track of the truck a bit, which he thought improved its stance. 

So far so good. The problem is, no mention whatsoever was made of the significant downside inherent in using wheel spacers. Moving the wheel outward by an inch and a quarter moves it that much farther from the wheel bearings, which—especially when exacerbated by larger, heavier tires—puts massive additional load on those bearings, load that will inevitably compromise their durability. Exactly how much is impossible to say (Bill said he’d be surprised to see bearings last 40,000 miles stressed thusly), but it is inarguable that the modification compromised Toyota’s engineering—that’s just simple physics. 

We see this sort of thing too often—laudatory articles boasting of improved ride, better handling, greater compliance, or enhanced power after the installation of extensive (and frequently expensive) replacements for factory parts. Unsurprisingly, these article are often shadowed by advertisements for those same products. (I went to the wheel spacer manufacturer’s site and looked in vain for any warnings of potential detrimental effects to installing them.)

Philosophical aside: Is the urge to “improve” an already decent product a peculiarly male obsession that can manifest itself on almost anything? I offer the legendary Colt Model 1911 .45-caliber pistol as an example. Designed as a reliable, powerful battlefield sidearm over a century ago, it transitioned effortlessly to a reliable, powerful self-defense sidearm for civilian use. But in the last couple of decades that urge to “improve” the 1911 has led to a bizarre market in which you can purchase a basic 1911 for around $500, then with no effort at all spend another three thousand dollars “improving” it. Not making that up—Google “Novak Full House Custom 1911” if you doubt me. Just as with our four-wheel-drive vehicles, many of those accessories actually do improve the utility of the pistol—ambidextrous safeties, tritium sights, modifications to allow feeding of modern hollowpoint ammunition, etc.—but in the drive to enhance the (perfectly acceptable) accuracy of the basic 1911, parts are added and components tightened in such a way that its intrinsic all-weather reliability—the raison d’être of the original design—is compromised. Nevertheless, Novak’s is so backed up with work they’re not taking new orders right now.

Where was I? Right. I’ve written earlier about the physics of tires and suspension lifts (here), noting the number of comments Roseann and I get from people who seem genuinely puzzled that we haven’t installed larger tires and raised the suspension on our Tacoma. When I point out the downsides of doing so, it’s surprising how few had any idea there were any. All they knew about bigger tires and suspension lifts was what they had read in magazines and advertisements. 

If you’re modifying a vehicle for extended backcountry travel, it’s vital that you investigate both sides of those modifications. Keep in mind Isaac Newton’s Third Law: For every action there is an equal and opposite reaction. Space your wheels outward to gain tire clearance and a wider stance, and you increase stress on your wheel bearings. Install larger, heavier tires and you decrease your braking effectiveness and increase stress on steering components. Modify your suspension for greater travel, and you force your axles and driveshafts to flex farther as well, with detrimental effects on CV joints and boots. (And, perhaps, other things: Bill Lee reports inspecting a Tundra lifted so far that the steering torqued the chassis at full lock because the rack could not travel far enough. Bill says, “I love lift kits. They keep me busy removing them and replacing parts.”)

View fullsize

Chris Collard, editor of Overland Journal, sent this along after seeing this post. Good advice.

If, after considering both sides, you decide the type of travel you do would be easier if your vehicle were modified, err on the side of caution. A two- or two-and-a-half-inch lift on a truck with independent front suspension is about the maximum practical without significant downsides. Note the angle on your front axles before and after the lift; you’ll see that they are now running at a noticeably greater angle all the time. Inspect your CV boots regularly. Avoid cheap lift kits that use blocks to raise the rear suspension. When it is moved farther from the spring, the axle will twist under acceleration and braking (this is called axle wrap). Some companies will happily sell you an additional product called a traction bar to help control this—why not just avoid it in the first place? Other kits use an add-a-leaf to jack up the existing rear spring pack. However, add-a-leafs can add stress points to the spring pack. We broke two add-a-leafs before wising up. Some tall front suspension lift kits come with brackets to relocate the steering linkage and even drop the differential—bits that solve one problem and create others. 

Remember: The number one function of an expedition vehicle is to complete the expedition. All the ground clearance and compliance and sharp handling in the world will do you no good if something major breaks. 

And finally, just so you don’t think I’m being superior about all this: In my gun safe is a heavily modified Colt Combat Commander .45 from Novak’s . . .

Knives of the Overland Expo

View fullsize

One of the best things about being on the setup crew and teaching staff of the Overland Expo is working around a lot of knives.

That is, it’s great to be among a group of people for whom a proper fixed-blade sheath knife is unremarkable daily wear—because it’s likely to be used several times every day. And boy do we use them during the five or six frantic days of prepping a couple tons of equipment and several tons of logs, the three dawn-to-dusk days of the show itself, and the relaxed but busy day and a half of take-down. Deployment might range from the plebeian but necessary task of cutting open taped shipping boxes (for which some of us will subtly substitute a Swiss Army knife so as not to sully our main blades with sticky residue) to the much more stylish—and difficult—test of slicing through Dyneema. 

This year I remembered to gather up a selection of what we’ll call W.O.U.R.N. knives (What’s On U Right Now) from the staff at dinner one evening, and snap a photo. Here’s a rundown of the batch, left to right.

1. Bruce Douglas has carried this AG Russell knife for well over a decade. Its three-and-three-quarter-inch blade is hollow ground from what was at the time one of the best stainless steels around: ATS-34. While eclipsed somewhat by newer alloys it’s still a fine steel. I know it holds an edge because Bruce has helped me field dress two elk with it. The hollow-ground edge makes it a very fine slicer, albeit a bit less robust for bushcraft tasks such as batoning. The scales are almost black cocobolo.
2. Volunteer Jayston Landon’s carry knife is a CRKT (Columbia River Knife and Tool) Chugash Range Hunter, with a three-and-a-half-inch blade that reminds me of a Scandinavian pukko. Big-knife aficionados laugh at blades this size; meanwhile, the Scandinavians shrug and continue to use their pukkos to field dress 800-pound moose. 
3. Nick Taylor carries this impressive Böker Vollintegral, with the longest blade in the group at four and five-eighths inches—still a modest size compared to a lot of the silliness out there. Its full-tang blade is made from 440C stainless—a prosaic choice in this age of wonder alloys (and at its premium price), but a reliable workhorse steel nonetheless. The solid bolster and pommel give the knife a fine, substantial feel, and the black micarta scales (comprising layers of linen in epoxy) lend both comfort and style. Finger grooves offer a secure grip in either hand. The blade combines a flat-ground spine with a hollow-ground edge.
4. A sublime example of pattern-welded steel (also known erroneously but persistently as Damascus), Andy Dacey’s knife is certainly the most beautiful here, yet it gives up nothing in utility, proving that a knife can be all things. Hand-forged in Japan, where the pattern-welded effect is called suminagashi, the core of the blade is Cowry X, a very high-carbon and chrome content steel, allowing it to be tempered to an astonishingly hard Rc-66 (most knives are hardened to Rc-58 to Rc-60). At that hardness steel can be brittle, thus the 32 layers of nickel steel on either side, which support the edge. The full tang is graced with desert ironwood scales secured with ornate rivets. This knife is flat ground, which should make it an exceptional slicer—and, given that steel, one that will not need sharpening for a very long time.
5. My own knife this trip was brand new, furnished to me by a promising new maker, Shannon Carter, whose business is called Fall Creek Knives. Shannon got my attention because he only makes working knives, no fantasy wall-hangers or zombie killers, and charges very reasonable prices. This bushcraft style uses very strong O1 tool steel in its four-inch blade, which is ground in a classic Scandinavian, or scandi, edge: Most of the blade is full-width; the edge comprises a single, wide bevel. This makes for easy sharpening in the field with a simple stone, as the edge is easy to orient at the proper angle. The scandi edge is also good for punishing tasks such as splitting kindling or even batoning cross-grain. Desert ironwood scales with black liners, and interesting pinning, along with acid etching on the blade, make this an attractive as well as useful tool. I’ll be posting a full review soon.
6. Duncan Barbour’s Bison Bushcraft knife makes all the others here look like drawer queens. It clearly shows the strenuous use of over a decade. Duncan shows it no mercy. He’s just as happy to use it on cardboard boxes as Dyneema—or cheese—but it still functions perfectly, thanks to tough O1 steel in the blade and an easily touched-up scandi edge, which is just about ready for some reprofiling to regain the proper flat bevel. The Bison Bushcraft knife is a near clone of the original Woodlore knife designed by Ray Mears in the 1990s. The original Woodlore design, made in England by Alan Wood, boasts a waiting list of several years and a price upwards of a thousand dollars; fortunately for those of modest means the best clones are every bit as good. 
7. And then there’s Graham Jackson. At first I thought I just caught him at an awkward moment, but no—this Leatherman Skeletool was his main cutting implement the entire week, and no one accused him of slacking off. With that said, a couple of days after the event, as we were picking up a few things at the Frugal Backpacker, Graham splurged on a very nice fixed-blade Helle Temagami.