I sometimes wonder how our industry ever managed the leap of faith it took to convert from gasoline to diesel engines or from tube-type to tubeless tires.
Having lived through much of the latter example, I remember several key observations.
The performance and cost-savings advantages of tubeless tires were obvious early on, especially to tire and OEM engineers. Still, the conversion went slowly. Granted, some time and convincing took place before these “potential” benefits were fully realized and appreciated.
In our industry, changes in major components are viewed with considerable skepticism until they are field proven “beyond a reasonable doubt.”
In this age of extremely competitive business, where success or failure is often no longer between the good and bad players, but between the better and best, all promising competitive advantages should be explored to improve operating efficiency. Current industry developments in single-wide tire technology might provide a good example.
Consider that dual tires came about more than eight decades ago but only by default. Materials and technology to support growing axle loads with a single tire simply did not exist in the industry at that time. Special deep offset wheels had to be designed for the rear dual fitments. Front steer axles then had to be widened to allow use of a common wheel on those positions.
Interestingly, the new generation of wide singles or super wides would ideally be fitted to zero-offset wheels, and axles would be widened by approximately four inches to allow a wider track, resulting in lower bearing loads, improved handling and stability compared to the setup currently being used. This hasn’t happened to date, since many users aren’t yet comfortable with the option of retrofitting duals disappearing.
Consider, also, that imprecise vehicle alignment and frailties of tire designs in early radials that made them susceptible to irregular wear made the option of tire rotation to different wheel positions attractive as a means to extend take-off mileages. For the most part, we’re beyond that now. Axle-specific tires are widely adopted for most line-haul fleets, and the time, trouble and expense of frequent tire rotations have nearly eliminated this practice in over-the-road service.
Operators with low tire costs tend to purchase high-quality products matched to the fleet’s equipment and service conditions and simply leave them on the wheel end until damage or wearout requires their removal, preferably for retreading.
This begs one more question: What do you do with worn steer tires if the drives and trails are converted to singles? One option would be to cycle them through city service or local delivery trucks. Another would be to sell them to the container chassis industry, where the issues of damage, maintenance challenges and theft will tend to discourage the use of singles for some time. Replacing the tube-type, bias-ply tires in many of these applications would upgrade the reliability, fuel efficiency and safety of this trucking segment.
Another issue with earlier attempts to use wide singles in place of duals was highway pavement loading. Some states had loosely worded, confusing and restrictive regulations that were interpreted inconsistently. Most, if not all, of those issues have now been addressed, and operators need not fear their rigs being shut down when crossing state lines. Also, driver acceptance of the new singles has been almost universally positive. This should be viewed as a positive factor, given the well publicized challenges of driver retention.
One question asked is what happens when a single tire loses inflation pressure and the resulting lack of “limp home” capability? Arguably, this should also be the case with duals, since loss of one tire will likely result in overloading its mate. However, this situation should become less of a concern with the availability of reliable, cost-effective pressure-monitoring devices and real-time communication of inflation issues.
Overall, modern singles should result in many over-the-road operators considering tires as more of a quality asset to be actively managed using life-cycle cost analysis, compared to commodity-purchasing thinking. As with most changes, timing is key.
Be aware that lots of questions about single-wide tires are currently being answered. Gathering high-quality information and regularly updating it are reliable ways to make sure you aren’t left behind.