One consistent swap topic we discovered while looking back through the last 499 issues of Four Wheeler was that having to do with traction aids. In the early days, the No-Spin from Detroit was the industry standard. However, over the decades a number of new devices have been invented to improve traction in the dirt. Four Wheeler has always been there to test them, from instructional stories on welding spider gears to create a spool, to full-on locker installation and reviews; our advice on this subject has all but dominated these pages. This article from the May 1979 issue, by Cliff Burch, spoke specifically about the Truetrac from Detroit, and the benefits of a clutchless limited-slip. The Truetrac is still widely popular today, and for most daily drivers it's the best traction aid money can buy. Competitively priced, a Truetrac will out-value and, in most cases, outlast any clutch-style limited-slip (LSD) on the market. Period. Another benefit to this type of LSD is that by simplicity of design, they have fewer parts to foul up, making them more reliable than some locking diffs.
We've seen some big changes with traction aids throughout the years. Perhaps the biggest has been the introduction of the selectable locker. With traction at your fingertips, this new breed of locker offers characteristics favorable for street and trail use. All, however, require driver input to operate, which may or may not be advantageous, depending on who's in the driver seat. Typically twice the price of a conventional limited-slip, these ultimate traction-adders are well suited for daily drivers and extreme purpose-built trail machines. The one shown here is an exploded view of the newest selectable locker on the market, the Electrac from Detroit Locker.
Back in Four Wheeler's first issue, a common problem associated with gearing (or lack thereof) was addressed. The article covered the subject of overdrives. Back then, the same problem existed that exists today. A 4x4 needs low gearing for the trail, and high-enough gears for reasonable highway travel. The problem back then was that very few options existed to actually change gearing. However, that all changed in the '60s when gear manufacturers began building optional ratios for most common axles. This was a good thing because it gave people the ability to run higher gears in the axles for highway driving, and allowed the low-range gearing in the transfer case to handle going slow.
It seems that no matter how often we've covered the subject, a reader will write in questioning us about a gearing issue. "Does my axle ratio need to be lower or higher?" "Will bigger tires prevent me from going slow on the trail?" "How low should I go?" In most cases, we try to find a happy medium that will work for both street and trail. However, the list of variables is long and the perfect combo isn't always black and white. That is why we have project vehicles. When Four Wheeler editors set up project vehicles, they figure out the best gearing combination for the particular scenario. We take into account the drivetrain, power output, favored terrain, and overall use intended for the project. With all the data at our fingertips, we choose whether or not to run-for instance-4.56:1 gears, an Atlas 6.0 transfer case, or both. Usually, editors pick vehicles that are popular at the time in hopes that the information provided in the article is indeed usable. Thanks to the wide range of gearing products available today, the perfect gearing is sometimes a matter of how much money you want to spend. Lower gearsets for the transfer case always seem to work well for those on a budget. Considerably pricey though still very popular, overdrive/underdrive units are sometimes the best way to handle gearing issues. Even more expensive yet are complete bolt-in transfer-case setups that in some cases can be doubled and tripled to squeeze a crawl ratio to a turtle's pace.