I recently hopped into a shiny new rental car.
In short order, I pulled to the side of the road after deciding that I was being distracted trying to locate the controls to perform basic functions such as turning on headlights, de-froster, radio, and map lights. I was used to reaching these things effortlessly in my familiar ride and wondered why each new car has to be different enough to be confusing. The short answer is likely that someone had a better idea — or at least thought they did. My question is, do most of the changes result in improvement, or are they change for the sake of marketing distinction? It wouldn’t be surprising if some engineer soon “discovered” that headlight dimmer switches could be cleverly located on the floor to free both hands for other activities.
Similarly, some clever ideas, covering a wide gamut from practical safety enhancements to sheer gimmickry have been tried in tires, mostly in non-truck applications, over the years. For example, chines have been used, primarily on certain aircraft tires, to direct water spray from wet runways away from jet engine intakes. These integral molded rubber sidewall sculptures are tailored to particular airframe bodywork and engine placement and have been used mostly on high performance military applications. They can be very effective in altering water spray patterns, but studies to expand usage to commercial truck tires seem to have been abandoned as under-chassis airflow and gap space (with re-sulting downdraft) between the tractor cab and trailer front have been identified as primary variables in the splash/spray from truck tires.
Then there are reflective tire sidewalls, which have been marketed from time to time, primarily on bicycle and motorcycle tires. Most have been high quality, embedded glass bead-type sidewall rings that greatly enhance nighttime or low-light conspicuity. The round shape is easily associated with a vehicle and would seem to be less likely confused with stationary objects than the linear tape stripes or point light sources commonly used as side markers.
Colored rubber laminates placed in the tread to indicate a certain tread depth, or a worn out condition, have been developed for passenger car tires, but usage has been minimal. Since radial truck tires are complex structures containing 12 or more different rubber compounds, engineers are reluctant to add another non-essential compound interface, especially one including a new or dissimilar compound family. Although this obstacle could be overcome with de-velopment efforts, another concern is that while such a feature might allow users to identify visually any tire reaching a designed in “pull point”, everyone else could also make the same observation, perhaps to the detriment of conscientious users whose tires achieved wear-out point in the middle of a cross-country run.
One feature that has been successfully transferred from small, light-duty tires to heavy-duty truck models is a self-sealing liner that allows the tire to stay in operation with even multiple punctures, so long as the injury does not impair the casing structural integrity. This works for typical nail holes and other small damages that would otherwise cause air loss and unscheduled downtime. Negatives are added tire weight, possible balance issues, and added costs.
Another interesting solution for enhanced winter traction, especially for icy road conditions, was offered by at least one large truck and bus tire manufacturer during the 1960’s. Each of the major circumferential ribs contained a molded in steel coil, similar to a long screen door spring, that wore with the rubber tread, always offering an exposed steel traction edge to icy surfaces. This reportedly allowed many buses to operate successfully without chains.
These are samples of innovations applied to tire designs over the years. In the case of truck tires however, the main emphasis has been on slowly evolving tried and proven concepts. The three exceptions come to mind: the introduction of radials, low profiles, and wide singles.