There’s a giant party happening in the world of CUV and SUV tires, and Cooper Tire & Rubber Co. doesn’t want to miss it.
With 175% more CUVs and SUVs on the road compared to 2009, and a corresponding 14% jump in the number of tire sizes to fit those vehicles, Scott Jamieson, director of product management for Cooper, says the tire manufacturer looks at its Discoverer SRX as the new launch pad for future products.
“It’s the fastest growing vehicle segment in North America, so we’re taking full advantage of the opportunity to participate there,” Jamieson says. “The SRX is the platform that’s established to keep up with that growth.”
Cooper bills the Discoverer SRX as a premium, all-season tire. It features a 65,000-mile tread wear protection warranty, as well as a 45-day road test guarantee. It comes in 36 sizes.
The silica-infused tread compound is new, and springs from a two-year development cycle and examinations of more than 100 compound possibilities. Lee Kanney, a tread compound development engineer, says silica — a sand-like element — bonds to the rubber better than carbon black. As a tire turns and beats the pavement the molecules stick together better and create less friction. Less friction results in improved rolling resistance.
“We’ve started using silica in many of our premium products, but with the SRX we’ve really perfected the balance between rolling resistance and grip,” Kanney says.
Fuel efficiency is helped, too, by the tire’s shape and dimensions. The Discoverer SRX is replacing the Discoverer CTS, and the SRX weighs less and offers more even pressure distribution across a relatively square footprint.
And while those internal upgrades are necessary to compete in the CUV and SUV market, Cooper really is counting on the characteristics consumers can touch to make this a top-selling tire.
The tire’s external qualities come from the work of tire design engineers like Chelsea Schuessler, and she says there are four key elements on the Discoverer SRX: Winter edge, Stabiledge technology, 3-D dimple sipes and a visual wear indicator.
Edges inside the circumferential grooves go to work in the winter, grabbing and holding snow which helps to improve traction on snowy roads. Stabiledge technology in the center grooves helps with soft handling as well as water evacuation.
Three-dimensional dimples inside the tire’s sipes allow the tire to flex as needed, but they prevent the sipes from separating too much. Wide open sipes are unstable and create a stair step of edges that disrupt the tire’s surface contact. The dimples allow the sipes to be cut much deeper than normal, which Schuessler says improves the appearance of the tire throughout its lifespan. “It also improves performance. With the CTS it was very easy to tell it was half worn. There were lots of blank spaces,” Schuessler says. “When the SRX is half worn it hardly looks it. You still retain all those biting edges.”
Technology aside, Cooper says consumers point to one detail over all others — the Wear Square, a visual indicator that gives drivers a simple checkpoint for tire wear. As the tire is driven, the sides of the square gradually disappear. The last side eventually appears as an exclamation point, indicating the tire has 2/32 of an inch of depth left and needs replaced.
Bruce Sanborn, product manager: “What’s great about the SRX is it has discernible features the consumer can physically see and point to, and the dealer then can explain the feature and benefit that it provides, like Wear Square.” ■
What does it take to develop a new tire?
A new tire, such as the Discoverer SRX by Cooper Tire & Rubber Co., doesn’t just fall out of the sky. Cooper’s technical team is comprised of 130 employees, and Heather Mosier, the manager of SUV, CUV and LT tire development, says the Discoverer SRX took two years to create. The process began in 2011 with surveys of consumers and tire dealers and by the end of 2013 the engineers handed off the product to the manufacturing plants in Texarkana, Ark., and Findlay, Ohio.
The first six sizes launched Sept. 1, 2014, in time to compete on two big stages: the Specialty Equipment Market Association (SEMA) New Products Showcase, and in a Consumer Reports test.
Cooper now sells 36 sizes of the Discoverer SRX with S, T and H speed ratings. Four V-rated sizes are coming in December and “a lot more” are coming after that to follow the growth of the CUV and SUV market, says Scott Jamieson, director of product management for Cooper. Here’s a breakdown of what it took to add the SRX to the Discoverer lineup:
- Benchmark testing of premium competitor tires.
- Eight unique development programs focused on critical details such as tread design, tread compound and tire shape and size.
- Laboratory tests involving 100-plus compounds. Twenty of those compounds were chosen for tire prototypes and testing before the ultimate mix was picked.
- Exhaustive testing in every conceivable environment: indoors, in the winter, on a track, on a fleet.
Inclined to grip: Cooper Discoverer STT PRO
There’s no indication Cooper Tire & Rubber Co. is changing its name to the Light Truck Tire & Rubber Co., but the numbers might warrant it. Quoting data from the Rubber Manufacturers Association, Cooper says it makes one out of every four LT tires sold in the industry.
As of June 1, there’s a new tire in the mix. Cooper is replacing its premium off-road Discoverer STT with the Discoverer STT PRO. The new tire features three-ply construction and a rubber rim flange protector to save the wheel from off-roading hazards. The tread compound is silica-infused, with cut- and chip-resistant additives.
Its non-directional tread pattern is built to clean itself of mud, stones and other debris, and sipes of varying depths are built in for better traction on wet surfaces and slick rocks. Cleats on the shoulder bite to provide maximum grip in mud as well as on inclines.
The Discoverer STT PRO is launching with 41 sizes with Q and R speed ratings and C, D and E load ranges.