Sumitomo Tire is introducing three new medium truck radials - the ST778 long haul steer tire, the ST 709 regional steer, and the ST938 long haul drive tire, all developed with S-Tech design technology.

The ST778 is a long haul steer tire. Designed for excellent handling and retreadability, it delivers exceptional miles to removal, according to the company. Flat Contact Technology delivers uniform contact pressure from shoulder to shoulder, enabling this tire to resist irregular wear across the full tread surface, especially in the shoulder area.

Redesigned shoulder grooves work with the wide, flat tread radius to control irregular wear, thousands of micro sipes protect the interior from punch wear, and 4/32nd stone ejectors protect the casing from damage. With a long-wearing tread compound on the outside and a cool-running base rubber compound on the inside, the ST778 provides resistance to irregular wear.

The ST709 is a regional steer tire with 20/32nd inch tread depth applied to a wide, flat casing for 10 percent more rubber volume and longer life in high-scuff applications. Thick curbing ribs shield the casing from sidewall damage and stone ejectors protect the casing from damage in the base of the groove. Chevron block center ribs with lateral sipes effectively cut water film on wet roads for enhanced traction and safety. The tire is suitable for high-speed regional transport, local P&D, school buses, equipment haulers, refuse trucks, and urban dump trucks primarily operating on paved surfaces.

The ST938 is a long-haul drive radial and features a super-deep 30/32nd-inch tread depth applied across a wide, flat radius to dramatically improve tread life. Bold tread elements deliver a combination of traction and rigidity, while the S-Tech Design casing yields long-term performance. Solid shoulders with a rigid interior tread block configuration on the ST938 help control heel/toe wear. Increased base tread rubber reduces heat generation while running at high speeds in a long haul operation. Diamond-cut block edges fight irregular wear and resist cuts and snags.

S-Tech Design is a collection of the most advanced technical features Sumitomo has to offer. Named for the S-shaped sipes in the ribs of the new ST778, S-Tech Design is the optimal combination of specific features in each new truck tire line working together for maximum performance and durability. S-Tech Design includes Flat Contact Technology, which minimizes irregular wear by controlling the contact pressure in the tire footprint to provide sufficient tread width and tread depth.

More info: www.sumitomotire.com