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Trail Rig Builder Basics

Posted in How To on June 19, 2012
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Building your own trail rig is a fun and exciting endeavor that for many evolves into a valuable learning experience and a family pastime. We understand how easy it is for those new to the world of off-roading to get caught up and overwhelmed with all of the aftermarket parts, endless build paths, and Internet chatter. We’ve always stood by the notion that learning to drive your rig and knowing its basic limits is much more valuable than any upgrade component you can bolt on. As you spend more time in the seat you learn what your rig needs, lacks, and can live without.

At 4-Wheel & Off-Road we believe in keeping things simple and creating a rig that always puts function above form. Though geographical regions, climates, and off-road goals all factor into your own list of needs and wants, many items cross over all aspects of truck building. So to help in your quest for creating your own personal version of the ultimate off-road vehicle, we’ve put together some of our most rudimentary builder’s parts and tips.

Matching your tires with your wheeling terrain is crucial. If you’re looking to crawl rocks and explore the barren desert, then an all-terrain can be an excellent choice. If there is any sort of wet dirt in your future, we suggest erring on the side of caution and investing in a set of mud-terrains. For most trail wheelers a mud-terrain radial provides a nice balance of street manners and off-road performance. Remember that when it comes to tires, bigger doesn’t always mean better. Your rig’s axles, powertrain, and wheeling environment are all important when picking out the right tires for your 4x4. A 33x12.50 is one of the most universal and safe tire sizes that you can put on a rig. While major mud riding will likely require something taller, we suggest starting small and working your way up.

Winch Way
A winch mounted to the front of your rig is one of the best tools you can have. Winch bumpers and basic mounting plates are pretty common aftermarket accessories and will pay for themselves in short time. Be sure to fit your rig with a winch that is rated for roughly 11⁄2 to 2 times the weight of your vehicle. We’ve had great luck with our Warn ( winches over the years, but many winch options are available from the aftermarket.

Keep It Low
Unless you are going for the King of the Mud Bog crown, we suggest keeping your rig as low as possible. A low center of gravity equates to a safer vehicle both on the road and off. We know not everyone is comfortable chopping up sheetmetal to clear room for larger tires, but there are still ways to keep your rig low with big cleats. Using bumpstops to abbreviate uptravel is common on all types of rigs. And when used correctly, bumpstops can help you balance squeezing on larger tires without destroying your fenders or sending your rig to the moon. However, when building your 4x4 with a low stance you have to consider skidplates for underbelly components as well as rocker panels. A low stance with low-placed bumpstops can also create a rougher ride and limit your rig’s suspension. A great goal is to set up your rig to sit mid-travel (e.g., if you have a 10-inch-travel shock it would be 5 up and 5 down). You often have to be creative with trimming, shock choice, and tire size to make this possible.

It’s easy to get caught up in the world of aftermarket bumpers, roof racks, and protective armor. Sure, giving your rig that bombproof Mad Max appearance may make it look like it can go anywhere, but the reality is that a heavy iron hide can weigh you down off-road. When looking at aftermarket bumpers and components, take weight into consideration. The more weight you add, the harder your rig will have to work to power you over obstacles and down the road. Also, don’t be afraid to modify and/or keep your factory bumpers. They might not look as cool, but less weight means more power and an easier load on your rig’s parts. Loading your rig with spare tires, parts, and every tool from the shed can add unwanted pounds as well. Sometimes a good plug kit, a few basic tools, and a sound understanding of what your vehicle actually needs to limp off the trail when disaster strikes are a great 4x4 diet.

Pan Protection
Keeping your 4x4’s center of gravity low means many of your rig’s vital components will be closer to the ground. Engine oil and transmission pans are some of the most vulnerable items. Underbelly skidplates, such as this Jeep Wrangler JK system from Evo Manufacturing (, are designed to prevent punctures and potentially expensive damage. They also add a little peace of mind next time you feel and hear scraping and banging under your feet. Rocker guards and rock sliders are also key players in the world of rig protection. Many bolt-on and weld-on kits are available from the aftermarket. Investing in a set of sliders can make the difference between opening your door or crawling through the window on Monday. For rigs with solid front axles, also keep in mind that your factory steering and differential cover(s) are likely to take abuse. Companies like Synergy Suspension (www.synergy make heavy-duty tie rods to beef up your low-lying steering bars.

Onboard Air
Going off-road usually means airing your tires down and up—a lot. Onboard air compressors, such as this OB2 100-percent duty cycle unit from Air-Zenith (, are an inexpensive and compact way of having air with you. For rigs with additional cargo space, an air tank can be fitted with your compressor for faster service and help with powering low- to moderate-volume air tools.

A good suspension system will increase wheel travel, ride quality, and off-road performance. There may be some give and take between on- and off-road manners, so do your research before investing in a kit. Modern 4x4s have pretty competent suspension systems that can work well in stock form. Don’t worry so much if your rig doesn’t have a huge lift kit or ultralong travel. Often good driving can outperform a fancy long-travel kit on the trail. We suggest starting basic and moving up from there. Don’t be afraid to change out components and build your suspension a little at time. Understanding the why and how your suspension works will help guide you in upgrading the right pieces and parts. Upgrading your shocks with high-performance units from companies like King Off-Road Racing Shocks (, Bilstein (, and Fox ( can make a huge difference. Many aftermarket shocks can be rebuilt and tuned specifically for your vehicle. This means you can have an

Fitting your 4x4 with front and rear locking differentials is a sure way to grab traction off-road. Locking your vehicle’s differentials allows all four wheels to turn at the same speed. For rigs that spend most of their time on the street, a selectable locker (one you can turn on and off) is a great option. Automatic lockers (ones that automatically engage) are generally more cost-effective but can have quirky handling characteristics and take a little getting used to. If you’re building your rig up one axle at a time, then we suggest starting off with a locker in the rear. Limited-slips can also work well for mild trail wheeling but will never replace or be equal to a locker. Keep in mind that lockers will also affect your steering. For example, a selectable locker, such as an ARB Air Locker, acts like a spool when it is engaged. This no-slip locked action can make turning the steering wheel off-road extremely difficult and sometimes impossible when the locker is engaged. An automatic locker, such a

Regearing your 4x4 to compensate for larger tires is not cheap but well worth it. Upgrading to numerically higher differential gears will place your power and rpm’s back to where the factory intended them to be. This will also alleviate some of the added strain on your transmission and give you more control and power both on-road and off. Regearing can also grab back a little fuel economy.

Off-road your wheels will be subjected to a lot of abuse. Steel wheels in general are extremely tough, but they are very heavy compared to their aluminum counterparts. On most of our extreme and dedicated wheelers we use aluminum beadlocks almost exclusively. The aluminum beadlock is a lightweight wheel that allows us to run single-digit air pressure without the risk of the tire breaking free from the wheel. Though steel beadlocks can work just as well as aluminum, they add weight. Your initial wheel investment may be more, but for dedicated wheelers the reliability and performance advantages will pay for themselves almost instantly.

Tool Bag
Don’t be the guy who borrows tools on the trail—be the guy who lends them. Before you go and spend money on an obnoxious sound system or a “Mississippi mud monster” windshield banner, buy yourself a quality tool kit. Both Craftsman ( and Kobalt ( make affordable entry-level kits that can get you moving in the right direction if you break down off-road. Toss in a couple of adjustable wrenches, a few screwdrivers, a roll of duct tape, electrical wire, a hammer, and a set of vise grips, and you are well on your way to having most of the tools you need on the trail. Is this all that you need? No. The more time you spend on the trail the more you’ll learn about your rig and what tools are most important to carry.

If you’re building your first 4x4 and you want a ton of power under the hood, buy something that already has a high-output engine. Engine swaps are not easy or cheap. The “keep it simple, stupid” philosophy is one to live by when it comes to power-adders. Most wheeling, especially on your average trail, doesn’t require a lot of ponies under the hood. Unless you’re heading for the dunes, monster mud pit, or Baja 1000 we say stick with the basics (cold air intake, programmer, exhaust).

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