Lets take a look at the commonly overlooked causes of excessive tire wear…
New shocks can extend the tire’s useful life by as much as 50%. Control of suspension movement is critical for safety, vehicle wear and tire life. As the Shock performance steadily declines with use, the suspension can no longer control wheel hop, creating a jack-hammer effect between the tire and road, severely reducing tire life. On average, shock performance drops off to where they are no longer offering proper dampening protection at approximately 150,000 miles on the steers and 250,000 miles on the rears.
The ATA-Truck Maintenance Council findings (RP643) reports that “Fleets have found it beneficial to install new shock absorbers when installing new tires, to maximize tire life.” Worn shocks cause excessive wheel hop which in turn causes a cupping wear pattern on the tire. When pairing worn shocks with new tires, tests have measured early signs of cupping wear after the tires were driven only a few miles on a rough surface. This irregular wear will feed on itself, and aggressively worsen until it eventually destroys the use of the tire. When new shocks were paired with new tires there was little or no measurable cupping for the life of the tires.
The benefits of balancing the steer tires are well recognized within the industry. Balanced tires reduce rolling resistance by decreasing tire sidewall flexing, tread squirming and friction and help prevent cupping. Studies show tire operating temperatures measured the balanced tire to run 8-25% cooler (dependent upon type of balancing system) than the un-balanced tire.
So why not also balance the drive and trailer tires? For rear and dual tires, the whole wheel assembly needs to balanced together and centered perfectly. The only means to accomplish this is with a dynamic balancing system, such as Counteract. An Auburn University TMC/SAE Type II fuel economy test performed on fully loaded tractor trailers in which all wheel positions were balanced using Counteract Balancing Beads, showed a 2.2% improvement in fuel economy (At 100,000 miles per year, that’s over 250 gallons of diesel). In addition a complete balanced wheel assembly improves tire life of upwards to 30%!
We all know the importance of proper tire air inflation. A 10 percent under-inflated tire will shorten tread life by 9 to 16 percent and reduce fuel economy between .5% -1% per gallon (At 100,000 miles per year, you’d use roughly an extra 84-168 gallons of diesel). To add insult to injury, under-inflation can cause excessive deflection limiting the usable life of your casing for re-treads.
Check pressure regularly. Until a cost effective automatic tire inflation system is available, consider using a Dual Tire Pressure Equalization System such as Cross-Fire. This system maintains equal tire pressure between the dual –tires, keeping them at equal diameters. This is important to keep the tires from fighting and dragging each other. Maintenance time is also reduced by having a single-point inflation and visual pressure gauge.