Most steer tires in a highway or regional application look very similar, but their internal structures and tread compounds may be quite different across different brands. Consequently, tire designers try to build in extra resistance to that sort of wear. Since steer tires are exposed to all sorts of external forces cause by misalignment, bad steering system geometry and other chassis-related abnormalities, they are the most likely to exhibit signs of irregular wear sooner than other wheel positions. “And steer tires in a regional or urban operation that make more frequent and tighter turns require greater scrub resistance through tread designs and rubber compounds.” “A steer tire is a free-rolling position and doesn’t have torque applied, so it’s designed to fight the onset of potential irregular wear, especially in highway operations,” notes Remec. Steer tires arguably have the most important job, so they tend to get more attention. Compare that to the other wheel positions that seldom support loads heavier than 4,700 pounds at about 90 psi. Some steer tires are rated for 6,500 to 7,000 pounds and require inflation pressures up to 120 psi in selected cases. Steer tires are unique in that they carry the greatest loads on the truck, often up to 2,000 additional pounds each, compared to a drive or trailer tire. They also have siping along the grooves to help promote even wear and often have a sacrificial groove in the shoulder area to help manage the onset of irregular wear across the crown of the tread.” “Tires designed for this free-rolling wheel position are generally designed with multiple circumferential grooves, usually referred to a rib tread design that provides water evacuation for wet reaction. “Steer tires need to be responsive to driver input and provide good handling feel while being comfortable and provide long, even wear,” says Karl Remec, Michelin North America business model leader – regional. They need stiff sidewalls to make cornering maneuvers and to keep the truck straight. Steer axle tires take driver input to direct the vehicle, and they are working constantly against 16, 20, 24 or more other tires that may all want to go in different directions. ![]() Asking one tire design to do all that would be a tall order indeed. They take a beating and they are generally ignored by drivers and even maintenance people. They still carry their share of the load and are constantly getting dragged over curbs and scraped across the pavement in tight turns. ![]() That doesn’t mean their job is any easier. Drive tires provide traction to get the truck going and keep it moving, while the trailer tires just kind of go along for the ride. It’s the steer tires’ job to keep the truck heading in the right direction. Features from tread designs to selected compounds are needed because the tires are tasked with different jobs. They’re all round and black, but there’s a reason why tires perform better in some positions and applications than others.
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