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There is a clear conflict between rolling efficiency and durability in terms of tire design. The advent of low rolling resistance tires was a boon for fuel efficiency and SmartWay verification, but the tire construction, compounds and tread design that make those possible weren’t always the most durable, which could lead to reduced miles-to-removal. Today’s tiremakers are currently trying to pull the opposed designs closer together as they experiment with new constructions, compounds and treads.
“In a nutshell, we have new compounds for long wear and a new casing that’s providing a more consistent footprint to help promote even wear,” explained Mahesh Kavaturu, marketing manager for commercial long-haul and regional products with Goodyear Tire and Rubber Co., during a recent online press conference announcing the new Goodyear Endurance LHS long-haul steer tire. “At the same time, we want to make sure our fuel economy is good. We are managing the trade-off you typically see between long miles to removal and fuel economy.”
Tread design, tread compounding and casing construction are the three major areas to consider when looking for the tire spec that fits your application. Luckily, the applications that your fleet tackles tend not to vary too often. That can act as a constant as you estimate tire costs. Then the choice comes down to your focus: Fuel efficiency or long miles to removal.
The key to a tire’s fuel economy can be found in its construction. Compounding, tread design and casing construction are three factors that tire manufacturers can adjust to help reduce rolling resistance.
For example, shallower tread designs generate less heat than tires with deeper tread designs. Tread compound works hand-in-hand with a tire’s tread design, and this intersection is where Goodyear put most of its focus for the Endurance LHS and its companion tire, the Goodyear Endurance LHD long-haul drive tire.
When evaluating tires, asking questions about tire compounds, construction and tread designs can go a long way in predicting how the tires will perform in their given position.
“If you look at the compounding for our steer tires, it’s different than that of the drive tire compounds,” Kavaturu said, “but the spirit is the same. We want to make ensure we enhance miles to removal with our Endurance products. But both tires are uniquely designed.
“Long-haul fleets are the biggest segment of the North American trucking market,” Kavaturu continued. “When it comes to tires, these companies measure every mile. And they want to get as many miles as possible out of their tire investment, without sacrificing other performance benefits like fuel efficiency, even wear and traction.”
Tire choice is a balancing act but Kavaturu provided some sound advice, which spoke to Goodyear’s current focus on its Endurance product lineup.
“It all depends on diesel prices.” he said. “If the diesel prices are about $4, then Fuel Max [Goodyear’s low rolling resistance tire line] might become more cost-advantageous, if you will, but Endurance products can be especially useful when the diesel prices are $3 or lower.”
The current average price of diesel across the country, at press time, sits at $3.153, according to AAA. Looking at another source, U.S. No 2 diesel retail prices were $3.25 in June 2018, according to the Energy Information Administration, part of the U.S. Department of Energy. (Change over time represented by the graph above.) “That’s only up a penny from May 2018, but is up 29% from June 2017 to June 2018,” said Bruce Kratofil, manager of market research for Babcox Media Inc. (publisher of Fleet Equipment).
With economy booming, freight rolling freely and diesel prices below $4, now may be the best time to focus on long miles to removal, but, as the diesel fuel price chart above shows, you’re never sure for how long. Best to keep an eye on diesel prices as you chart your tire spec’ing plans into 2019.