lectric, gas, cable and telephone providers have some specific tire needs, and the requirements may change with some evolving industry trends. Most are locally domiciled and serviced by a single shop, so inflation pressure maintenance and routine visual inspections for cuts, wear, and other out-of-service conditions shouldn’t pose a problem.
Typically, the trucks are used for routine new utility line construction, upgrading and maintenance. However, much of this equipment sits idly on standby to handle emergency repair operations.
Consider The Differences
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 bet-
ween these high mobility tires and the deep-tread, high-mileage drive tires typically found on over-the-road trucks, which are designed more for long treadwear on smooth highway surfaces than traction on marginal terrain. The high mobility tires generally have a greater percentage of void area in the tread and use open or broken shoulder tread lugs.
Some tire makers offer these aggressive designs as highway tires for mild on-/off-road duty, and also in more robust models with heavier duty casings for more severe service. With either choice, some reinforced sidewall design, such as heavy gauge scuff ribs or a cut-resistant compound, provides extra protection.
Weight and Stability Sensitive
Most utility service trucks are based on regular highway chassis, but are fitted with crew cabs, lift buckets, outrigger stabilizers, digging augers, tool storage cabinets and other devices. These additions increase tare weight, but also significantly alter weight distribution and center of gravity.
As a result, these trucks may be more sensitive to stability than regular freight hauling trucks, especially on unlevel terrain. Lower aspect ratio (tire section height/tire section width) tires generally offer higher lateral spring rates, and therefore improved lateral stability. The chart below shows a comparison of tire sizes with similar load capacities.
Note that tubeless tires have lower aspect ratios than their tube-type counterparts. They are now standard on virtually all new vehicles, but should be considered, along with properly selected tubeless rims or wheels, for retrofitting on older trucks.
A special caution is that medium tread depth traction tires may provide a stability or “road feel” advantage over deeper-tread models on marginal vehicles, usually the result of unique equipment being fitted to the chassis.
A recent trend of downsizing chassis size for some utility service applications has resulted in trucks with reduced track widths and lighter duty suspensions for line maintenance tasks previously performed by heavier duty (and more expensive) models. These vehicles are typically based on pick-up chassis designs or other new Class 4-6 truck types, and may be very cost effective for selected jobs.
It’s important that tire selection for these trucks also consider the added loading, weight distribution and stability requirements of lift buckets and other auxiliary equipment. When possible, 70 or 75 aspect ratio tires are preferred on many of these smaller trucks.
Several manufacturers now offer heavy-duty steel casing/steel belt radial designs in 16- and 19.5-inch rim diameter sizes, and more sizes are likely soon. Some of these trucks feature all-wheel drive and require traction tread designs with matching diameters on all wheel positions.
Retreading programs are cost effective and work well for utility service fleets, provided the casing sizes, tread designs and tread depths are selected with the same careful consideration as new tires.®′