Irregular wear may have no where to hide on the next generation of Bridgestone/Firestone drive tires.
The tire maker gave dealers a glimpse of six prototype steer tires and five prototype drive tires at its 7th annual BizCon commercial dealer meeting April 23-25 in Las Vegas. Though all of the tires are being tested in fleets, company officials stressed the tires may or may not reach the market in their current form.
But as they're being tested now, some of the drive tires have the Equalizer Rib design that Bridgestone/Firestone has given a prominent role on the steer tires it launched this year. The equalizer rib is a thinner, shallower rib that sits within the tread to absorb the bulk of the forces that cause irregular wear.
``This is designed to sacrifice itself to keep the rest of the tire healthy,'' said Guy Walenga, engineering manager for North American Commercial Products at BFS.
Many of Bridgestone/Firestone's new tires this year expanded their use of the equalizer ribs and other irregular-wear-preventing technologies. The prototype drive tires are the next possibility, officials said.
``They are still exploring it to see its potential,'' said Daniel Allen, product planning manager for BFS. ``It's a technology that works, and it works so well they're going to utilize it to the best of their capability.''
Still, he said irregular wear is not as common on drive tires as it is on steer tires, so whether the construction will reach the market is unclear.
Mr. Walenga said many of the potential steer tires also further embrace the technology. He said irregular wear is one of the main factors steer tires are removed before their time.
``You're always trying to minimize that,'' he said.
In the drive tires, one prototype had equalizer ribs running parallel to the rest of the tread, like those ribs currently offered on steer tires. But one prototype had short ribs running between the tread blocks to control irregular wear on the shoulders. That tire had the feature on only half of its tread, so any effect on irregular wear could be measured easily during tests in fleets, Mr. Walenga said.
The tires and their rubber compounds also are designed to have low rolling resistance. That goal is aimed at reducing fuel costs, which have been rising steadily for fleets. Mr. Walenga said the prototype tires all had new compounds, though he could not elaborate.