Cooper Offers New Roadmaster RM351 HD in Two Sizes

Feb. 20, 2019

The new Roadmaster RM351 HD from Cooper Tire & Rubber Co. comes in two sizes: 11R22.5 and 11R24.5, in load range H.

Engineered for mixed-service applications such as construction, logging and mining operations, the tire is designed for both on- and off-road driving.

The Roadmaster RM351 HD is a full inch wider than its predecessor, the RM300 HH, with a 20% larger footprint. The company says that coupled with its deep 32/32nds tread depth, the RM351 HD provides up to 25% more miles to removal – depending upon the application.

“That’s a big step forward in tire performance for our Roadmaster customers,” says Gary Schroeder, executive director of Cooper’s global truck and bus tire business. “By going wider, we spread the weight over the tire to gain better mileage, while also improving traction. It’s a win-win.”

To help ensure long tire life, tie bars between the outside lug and the shoulder, along with shoulder grooves that are linked and interlocked, help ward off tire squirm and irregular wear. The sidewall is extra thick with a curb bar protector to help protect the casing from cuts and scrubbing.

For traction and long-life performance, the tire features five lugs that have an open pattern to minimize stone holding while enhancing traction. Stone ejector ledges, coupled with angled grooves, also help prevent stone drilling. “That’s a key feature of the tire as it will be used off-road where sharp stones can be a tire’s worst enemy if they’re allowed to drill into the casing. The way we designed this tire helps preserve the casing for multiple retreads,” Schroeder added.

The Roadmaster RM351 HD’s casing itself is extremely robust, with four-belt steel design construction. Cooper provides a six-year, two-year tread warranty on the RM351 HD. “The casing we’ve developed for this tire, along with the warranty, provide life and cost efficiency beyond the original tread,” says Schroeder.

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