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Dual Purpose 4x4 Truck Upgrades - Dual-Purpose Building

Posted in How To on December 1, 2008
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How you build your 4x4 depends a lot on where you live, the terrain you drive, and what parts are available to you. But as we returned from our Ultimate Adventure trip we started contemplating the Anywhere Wheeler. We all know that it's easy to build a dedicated wheeler to one type of terrain-rock buggies rule rocks, sand rails are king in the dunes, and mud trucks power through slop that would drown other rigs. But what would be a good recipe for a do-all machine?

Maybe you want to hit the road for a month (better yet, a year) and go see the country, taking on trails and terrain from across the nation. Though you may not outwheel the locals on their home turf, you want to at least be able to hang with them and attempt their toughest obstacles. When you're done wheeling it might be nice to just unlock the hubs and cruise down the road without the headache of a truck and trailer. Sounds like we're describing Ultimate Adventure, eh?

Consider this a recipe for building a UA-ready truck. We've seen a lot of different stuff, and though anything can be made to work for this type of cross-trainer wheeling trip, some things work better than others. We're not saying this is the only way to build your truck, but if you want it tough, reliable, easy to fix, and still super capable, then consider these upgrades.

We've seen crazy coil links work great off road, but we've also seen more than a few rod ends peel open and send expensive coilover shocks straight to the Dumpster. At the same time, leaf springs can be twisted into pretzels in seconds. We recommend overbuilding your suspension, using big link joints, and don't forget the antiwrap bars to keep leaves alive. We've had suspension components peeled off frames and axles over the years, but if you build it tough and keep it as low as possible, you'll be sidehilling like crazy, dune running, and still be clearing big rubber for the mud holes.

It's hard to beat the combination of a Dana 44 or 60 front and a Dana 70, a Ford 9-inch, or a 14-bolt in the rear. Yes, lighter axles have survived for years, but these axles can be repaired anywhere (if they break), and they are supported by a huge aftermarket. The 70 has a smoother bottom to help clear rocks, but we also like the 14-bolt for its pinion support and commonality that results in spares in most junkyards. Our favorite setup is a 4.88 to 5.38 ratio with either ARB or Detroit Lockers, depending on your personal preference. Leave 'em full width, swap in some drive flanges for extremely tough rockcrawling days, and use at least 4 1/2 backspacing to keep the track width within reason.

Our UA trip is sponsored by BFGoodrich Tires, so you'll see their rubber on most of the trucks on the trip. But it's important to remember that for all-around use, a good knobby mud-terrain rules. We'd recommend a radial for smooth street days with tough sidewalls, and don't forget a spare. We've found that 35s to 37s on any wheelbase under 100 inches and 37s to 42s for any wheelbase over 103 usually result in a good breakover angle.

Body armor is a tricky decision depending on your vehicle and your outlook on body damage. You want as little as possible so you don't get caught up on big bumpers or side steps, but enough to still protect the body and slide over obstacles. The front bumper needs to be solidly mounted and housing a winch with pulling power 11/2 times the weight of your truck. Trust us, we've tried to pull 7,000-pound trucks with 9,000-pound winches and it wasn't fun.

Start with Tube?
One more thing about where to start. As you know, tube buggies are now an integral part of the wheeling community and they can make great dedicated or dual-sport wheeling rigs. However, getting them past the long arm of the law will take more work than it is sometimes worth, especially when you want to drive them on the street. (Future Fun Buggy articles will show you how we did it.) If you have a truck and trailer then just tow and forget it, otherwise you may wish to start with an OEM platform, or start with a factory frame and tube off of that like this Jeep TJ buggy.

Driveshafts can make or break a wheeling trip, so our advice is to check that they don't bind or separate under extreme articulation. Bringing a spare set, or at least a spare rear, allows you to swap in the balanced shaft for road days, then run a thick-wall version for trail days. Run your links or antiwrap bar to provide rock protection.

Beadlocks help in just about any terrain because tires work better at low air pressures. We've remounted tires in the mud and it's almost as much fun as a stick in the eye.

Where To Start
We've spotted, pushed, pulled, and dragged every known vehicle up the trail, and the thing to remember is that no matter what vehicle you start with, there is a trail out there you can walk through and another you'll be stuck on for days. Whether you go lightweight Suzuki style or giant four-door fullsize, you can have fun. The smaller you go, the lighter all your parts can be (and the less fuel you'll use), but sometimes wheelbase can make up for that extra mass. Just remember you need room for anyone and anything you want to bring along, and if that includes your 200-pound twin brothers and all their food and camping gear, then a Samurai might start looking a bit cramped.

Steering And Stopping
Full hydraulic steering is all the rage these days and we have to admit it's pretty darn impressive. In fact it would be our choice for a dual-sport trail rig, as long as it never sees the street. We know many who have driven on the asphalt with full hydro, but we like the security of a hydro-assisted steering box for those rigs that are on the same roads as busloads of little kids.

Drivetrain choices are going to be debated until we're all red in the face and out of beer, but there are certain things that work better. First, when it comes to engines, stock is hard to beat for long-term reliability. Race parts are cool, but when you want it to run cool, find parts at any backwoods parts' house, and be fixable with a rock and a hammer, then bank on stock. With the price of fuel many of you may cringe, but having a V-8 is really the best way to go with this buildup. They have torque, they have power, and they can run great off road over a variety of terrain, plus the current V-8s are getting great fuel economy. Find one with easy-to-install factory fuel injection and hopefully you'll never need to open the hood.

Transfer Case
Gearing is the great wild card-the more options you have the more places you can go. We're huge fans of doublers and multispeed transfer cases for an all-around vehicle. This allows street and trail gearing as well as wheel spin for mud and sand and creepy crawly rock gears. We don't see many factory 2:1 low ranges in the best-performing all-around trail rigs. Gearing is like limbo; you need to go lower to win.

No matter what terrain you hit, certain items should be on your required driver safety list. A rollbar is better than a steel or rag top (we've seen rigs roll on flat ground); a first aid kit to patch up boo-boos; at least two fire extinguishers, as gas and electrical flames can be hard to put out; and quality tie-downs for everything from driver and passenger to batteries, tools, and spare parts.

Here is another area of undying discussion-automatic versus manual transmission. We've seen both work and both fail so we're leaving this one up to you. If you go auto, install a big cooler and a temp gauge. If you go manual, make sure you're full of lube, have a fresh clutch, and if possible get an Overdrive.

This Week's Dream
Like any gearhead we are constantly dreaming up new wheeling rigs that we may never build. Here is what we would build this week if money were no object and we had all the time in the world: Find an early Bronco and cut it off behind the doors and make it a pickup cab. Maybe narrow the tub depending on your favorite trails. Behind the cab we'd add a 4- to 6-foot aluminum pickup or Australian-style flatbed. A GM 5.3L LS engine out of a late-model GM truck, a C4 automatic with Advance Adapters shorty tailhousing kit, and a four-speed Atlas would supply reliable power and gearing galore. Front axle will be a full-width Dana 60, rear would likely be a 9-inch, maybe a 70 depending on cost, and gears would be 4.56 or 4.88 since the Atlas makes up for the higher gears. Wheelbase would be about 103 to 110, tires would be 37s or 40s, depending on what type of deal we could find. Front coilover shocks, rear leaf springs. This truck would be fast, streetable, narrow enough for tight stuff, yet roomy enough for long trips. It would be convertible for fun summer wheeling and have a bed so it could be useful any time of the year. Plus the same recipe could be built out of a Land Cruiser, Jeep, Rover, or Scout. Of course next week we'll have a different all-around dream build.

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