The popularity of heavy-duty tubeless radial tires in sizes designed for lighter commercial trucks (Class 3-5) has increased dramatically in the last several years. The light- and medium-duty applications that benefit most from the more robust tires are those that accumulate high mileage and have frequent stop-start duty cycles — in short, those that are tough on tires.
With rim diameters of 16- to 19.5-in., they differ from their traditional light-duty counterparts by having a lot in common with the OTR radials used on Class 6-8 vehicles, including heavier sidewall and shoulder areas and steel body plies. These smaller heavy-duty tires are also designed to deliver long original treadlife and multiple retreads.
You can also add cost to that list. But making that investment up front can mean significantly lower life-cycle costs, provided that good maintenance and retreading are integral parts of the tire program.
Frequent inflation checks, visual treadwear monitoring to assure timely removal, and professional quality puncture/damage repairs are the cornerstones of commercial tire maintenance. All are necessary to protect the basic tire casing for future retreading and to avoid unscheduled downtime.
Successful retread programs are a bit more complex. Most experts agree that the single most important step in retreading is a high-quality incoming casing inspection prior to actual retread processing. A variety of non-destructive tests are available to identify and mark punctures and other areas where repairs are needed.
Casings that are damaged beyond industry repair limits or that are over-age can be culled out before any additional investment is made. The industry has also made a good deal of progress recently in the ability to detect casing abuse due to overloading/under-inflation during prior service life so that early retread problems related to casing failure (vs. retread failure) can be minimized.
A second area that should receive attention is the need for equipment and materials specifically tailored to the smaller size tires. These vehicles typically experience high frequency and severity of wheel cut angles in their delivery duties. Therefore, tread compounds that will resist high abrasion scuff angles, heavy braking forces, and the high acceleration torques generated by modern diesels and short (numerically higher) axle ratios are required. Also, robust and simple tread patterns are generally preferred.
Careful selection of specific retread suppliers is also important. Start by choosing companies with well-established reputations for high-quality products and service. Talk to other fleets that have used their services. An unannounced tour of the facility where your tires will be processed can also be enlightening and help in the final selection decision. Discussions with potential retreaders should include warranty responsibility, especially in the “gray” area of casing vs. retread problems.
The requirements for successful retreading of this new generation of commercial light-truck tires are very similar to those for larger tires. There is one more thing to think about, however. Be sure to confirm that the retread provider has the equipment and material sources needed to process the smaller sizes, and that it can provide the specific tread rubber sizes, compounds, and pattern designs unique to these applications.
An excellent source of information on retreading is the Tire Retread Information Bureau (TRIB). This organization can be accessed via www.retread.org, or by using e-mail addressed to [email protected].