Dunlop raises concerns over new California tire rules

Rancho Cucamonga, California – Dunlop Tires North America (DTNA), part of Sumitomo Rubber Industries, has raised concerns over the recent decision by California policymakers to introduce new efficiency standards for replacement tires. (ERJ report)

While recognising the environmental objectives behind the decision, DTNA said that the new rules “do not fully address the complexity of tire design since a tire is not developed around a single performance characteristic [rolling resistance].”

“We do not discount the importance of those objectives, nor do we oppose responsible efforts to improve the efficiency of the products our industry manufactures,” said DTNA in a 19 Aug statement.

However, it noted, depending on the application, a tire is engineered to include a balance of rolling-resistance, traction, durability, handling, load capability, weather performance, ride, noise and cost.

“California must be equally careful to ensure that improving one of those characteristics does not unintentionally compromise the performance, choices, affordability and competition that consumers depend upon from the replacement tire market,” stated DTNA.

The ultimate measure of this programme, the tire manufacturer argued, “should not simply be whether California achieves lower tire rolling-resistance.

“It should be whether California achieves a better overall outcome for the environment without creating a material adverse impact on consumers, consumer choice, competition or trade.”

DTNA went on to highlight the differences replacement tires and OE tires, which are developed in close cooperation with vehicle manufacturers for particular vehicle platforms.

OE tires are engineered “to satisfy a specific combination of performance requirements established during development of that vehicle including fuel economy regulations.

While ensuring lower rolloing resistance is "a legitimate engineering and regulatory objective," DTNA said it is a departure from optimising the tire for individual consumers. 

“That distinction is fundamental to DTNA's concern,” the company pointing to other consumer priorities, such as tread-life, wet-traction, durability, off-road capability, handling, price, or total cost per mile.

“Replacement tire regulations should preserve the ability to choose products appropriate for different vehicles, applications, budgets, and environments,” insisted the company. 

Concluded DTNA: “California should therefore evaluate the complete economic and environmental lifecycle of a tire – not rolling resistance alone.”