High-mobility tires most suitable for utility trucks
Utility-service trucks, such as those used by electric, gas and telephone construction and repair providers, have very specific tire needs. Since most are locally domiciled and serviced by a single shop, maintenance of proper inflation pressure and routine visual inspections for cuts, wear and other out-of-service conditions shouldn't pose a problem if proper training and support are in place.
These vehicles are typically used for routine construction of new utility lines, as well as upgrading and maintaining existing lines. However, much of this equipment is on 24-hour standby to handle emergency repair operations, including damage caused by storms or accidents.
In all but the largest urban areas, aggressive traction tires are preferred on drive axles to assure mobility in these go-anywhere/do-anything situations. It's important to distinguish between these high-mobility tires and the deep-tread, high-mileage drive tires found on over-the-road 18-wheelers, which are designed for long treadwear on smooth highway surfaces rather than for traction on marginal terrain.
High-mobility tires generally have a greater percentage of void area in the tread and use open or broken shoulder tread lugs. These aggressive designs are available in a "tamer" version for highway tires that have some mild on-/off-road duty, as well as in robust models with heavier duty off-road casings for severe service. Both have a reinforced sidewall design for extra damage protection. The best choice for you depends on local terrain and soil conditions. When making these decisions, it's always a good idea to get advice from experienced tire professionals in your area.
Most utility-service trucks, which are based on regular highway chassis, are fitted with a variety of unusual equipment such as crew cabs, lift buckets, and outrigger stabilizers that not only increase tare weight but also alter weight distribution and center of gravity. As a result, the trucks may be more sensitive to stability than regular freight-hauling vehicles, especially on terrain that's not level. Tires with lower aspect ratios (tire section height/tire section width) generally offer higher lateral spring rates and improved lateral stability.
Tubeless tires have lower aspect ratios than their tube-type counterparts. Although standard on most new vehicles, they're often overlooked when it comes time to put replacement tires on older trucks.
The recent trend toward downsizing chassis size for some utility trucks means vehicles with reduced track widths and lighter duty suspension components for line maintenance tasks previously performed by heavier models. Typically based on pickup chassis designs or other new Class 4-6 truck types, these vehicles can be very cost-effective for selected jobs.
When selecting tires for these trucks, be sure to consider the added loading, weight distribution and stability requirements of lift buckets and other auxiliary equipment. Tires with aspect ratios of 70 or 75 are preferred on many of these smaller trucks. Several tire makers now offer heavy-duty steel casing/steel-belt radial designs in 16- and 19.5-in. rim diameter, and more are expected. In addition, since some of these smaller trucks feature all-wheel drive, they require traction tread designs with matching diameters on all wheel positions.
Another thing to keep in mind when you're selecting drive tires for vehicles with a high center of gravity is that medium tread depth traction tires may provide a stability or "road feel" advantage over deeper tread models.