The Evolution Of Trail Tires - 500th Issue Then & Now
From bias-ply to radial-and back again
Things in the world of trail tires have changed drastically since the traction tire debuted in 1908, and especially so once recreational four-wheeling began gaining popularity in the '40s and '50s. As with so many other things, the past decade has really been a time of innovation and refinement. In the early days of four-wheeling, 9.00-15 recaps on two welded-together rims was the hot ticket for flotation. No wheel manufacturers made wide rims yet, and the military NDT treads were obviously not the ideal tire for staying on top of sand or loose dirt. It was largely the farmer's and hunter's need to get around on soft ground that drove the pioneers to invent out of necessity. Mud runners had the Firestone Super All Traction, usually in the 7.50-16 size, which fit just fine on a stock 16x4.5 Jeep CJ rim. You just couldn't steer much.
As late as 1965, Con-Ferr advertised "Wide wheels & tires" in Four Wheeler, although they were 15x7 or 14x7 wheels with 9.50-15 or 9.50-14 tires. Wide?!? Well, for the time, yes, and they were "new first line tires"-with whitewalls. You got five for $277. Spending just a few dollars more could buy you comparatively huge 11.00-15 Armstrong flotation tires (looking much like airplane treads and not necessarily DOT-approved) and rims over 9 inches wide. Of course, there was a $7.50 core charge on the wheels. Four Wheeler's Willie Worthy had his own jig for widening wheels (after cutting them apart on a lathe) by welding in a rolled steel band. You pretty much had to make your own "bolt-ons" back then, and grooving tires was more of a need than a want in those days.
Also in 1965, Armstrong introduced bias-belted tires with fiberglass belts, and BFGoodrich produced the first radial in North America (invented 16 years earlier by Michelin), but those were still all-highway tires.
With a definite demand to fill, from little known individuals like Dwaine "Birddog" Franklin in his small Yuma, Arizona tire store to eventual celebrities such as Dick Cepek, people were working on creating more capable trail tires. They convinced Armstrong to make one of its farm tires in a highway-rated version, and the 11.00-15LT Tru-Trac was born. Dick Cepek even managed to have Denman modify industrial forklift tires for 15-inch rims, resulting in the Quiet Giant. According to Willie Worthy, Bobby Dunlap similarly created the Ground Hawg. By this time, there were also aluminum rims available, although not yet particularly light or strong, so the far less expensive (and painfully heavy) "white spoke" steel wheels were still the most popular.
In 1976, BFG introduced the All-Terrain T/A (followed by the Mud-Terrain T/A in 1980), which started popularizing the radial for the four-wheeling market, but it took until 1985 before radials dominated the original-equipment LT tire market. Another two years went by, and then the replacement market was also mostly radials. Meanwhile, Interco was busily expanding its line of Super Swamper bias-ply tires for enthusiasts.
Starting with the first-ever L78 tire in early 1970-a Swamper, which developed into the immortal TSL Super Swamper in the mid-'70s-Interco was working on mud tires while most everybody else was focused on flotation. Seems that Interco was also among the first to try making a mud tire that was usable on the street, noise-wise.
There is an enormous selection of radials available, and in an amazing amount of sizes. Exotic tire-building techniques and multi-segment molds allow for rounder and even better tires than just a few years ago-and much bigger ones. Computer-aided tread designs have helped produce mud tires that emit less noise than what some all-terrain tires did-or do, for that matter. Handling and tread life have also increased quite a bit lately. At the same time, special, sticky tread compounds are becoming available, not just for the "professional" rockcrawlers. Tires are being made especially for 'crawling, which is very impressive when considering the relatively small portion of four-wheelers who are dedicated to rockcrawling-and even more so since trail-type tires are only a really small piece of the tire market in the first place. But, it seems we're in a transitional period again and about to (at least partially) backtrack to old-tire technology.
While radials are steadily improving, more and more four-wheelers are returning to the bias-ply construction. A step in the wrong direction? No, not at all. Or, at least no more than replacing an IFS with a live axle-some of the old stuff simply works better for demanding four-wheeling. Consequently, the bias-ply tire is making a comeback because of its trail-friendliness, superior conformability, and sidewall strength. Plus, tire grooving is back in fashion, but this time it's to achieve even more tread flex, and in search of the perfect contact pressure.
Whether bias or radial, with much improved tires there's no longer much of a need to shove a couple of sleeping bags into a mortally wounded tire to get back to camp. Better sidewalls, good glue-less plug kits like Safety Seal, and affordable compressors are standard trail equipment now, making the spare tire largely ornamental.
With tire technology improving by the week these days, we'll surely see lots of interesting innovations and improvements. Unfortunately, we'll also end up with some less desirable things: Government-regulated tire pressure monitors, for example-an anti-Darwinism device meant to save the butts of lawsuit-happy people who don't know to keep correct tire pressure in their street-only SUVs. These monitors will likely set off all kinds of alarms when we air down for the trail. We can only hope that, at the very least, the manufacturers will see fit to make selecting low-range shut them up-or there actually will be a reason for loud stereos on the trail.
Hopefully, the trend with ridiculously short sidewalls will go away, and the corresponding overweight large-diameter wheels will go the way of angel-hair interiors. Of course, those tires you can still (but probably shouldn't) air down, which isn't the case with the new "Tweel."
Yes, Michelin is working on a combination wheel/tire that doesn't hold any air, or even have sidewalls. OK, no more sidewall failures is a positive thing, and we understand that it's possible to chrome the elastomeric polyurethane spokes that replace the traditional tire casing, but is that really what we want for trail use? A tire that you can't air down isn't exactly the most traction- or comfort-friendly trail invention we've heard of.
Perhaps the above will become a moot point as we may all have to run Low Impact Environmentally Friendly (LIEF) tires soon to even be allowed to 'wheel in certain places. More trail-friendly treads could become a must and, ironically, they could very well be constructed and look much like the Armstrongs and Deltas of the early 1960s.
Whichever way things go, it's a safe bet that we'll have an even larger selection of ever rounder and more capable tires as they become more specialized yet for their intended use-and luckily, that includes trail tires.