Dunlop Tires North America Inc. (DTNA) executives are reinforcing their opposition to California’s replacement tire efficiency mandate and remain concerned over the regulation’s potential impacts on manufacturing capabilities, tire value, safety and product availability.

During the company’s second virtual webinar on the state’s ruling, Darren Thomas, president and CEO, Ken Hsu, vice president of marketing, and Rick Brennan, associate vice president of TBR, outlined DTNA’s recent analysis that inspects how possible engineering changes needed could affect tire price, tread life, overall performance and cost.

Since the California Energy Commission (CEC) recently approved the Replacement Tire Efficiency Program, Phase 1 will begin in 2029, followed by more stringent requirements beginning in 2033. The CEC says the standards will reduce energy use without adversely affecting tire safety or service life. It estimates an incremental cost of $1.50 per tire during Phase 1 and $6.50 per tire during Phase 2. For a typical gasoline-powered vehicle, the agency projects $179 in fuel savings over the life of a set of tires.

Different products with different outcomes

From Dunlop’s perspective, the state’s estimated cost savings does not accurately predict what the replacement market could be like when tire manufacturers redesign products to meet the new standards. 

While some consumers may see savings when purchasing tires, others may face higher costs and key performance tradeoffs that can vary by vehicle class, tire type and tire size, Thomas, Hsu and Brennan warned. 

DTNA’s analysis compares three different replacement tire scenarios – an economy passenger tire, a premium passenger tire and a light truck tire – to explain how each segment could have drastically different outcomes as a result of the rolling resistance mandate. As MTD previously reported, DTNA says the examples are sensitivity analyses based on possible engineering responses, rather than predictions of what individual tire manufacturers will ultimately do.

As MTD has reported, the company’s example of a common 195/65R15 economy tire illustrates how an increase in material and engineering costs, an engineering approach that reduces the tire’s service life by 20% and an increase by roughly 51% of its cost per mile could ultimately reduce the CEC’s predictions of a $153 net consumer benefit projected for Phase 2 to nearly $14 or less.

Dunlop’s analysis pointed out that the company isn’t making predictions for dramatic price increases or reductions in service life. Those are assumptions the tiremaker is using to illustrate how the economics can change depending on the engineering choices manufacturers make. The team said this example pinpoints concerns for dealers with price-conscious customers.

DTNA’s other two examples from its analysis show why the California mandate does not affect all consumers the same way.

While the company explains a premium tire may be able to absorb more advanced materials and technology while keeping its service life – which could then benefit consumers as the CEC predicts – a light truck tire example could produce a different outcome.

DTNA says increasing tread depth sufficiently for a light truck tire to qualify a product for one of the regulation’s exclusions could potentially improve tire cost per mile, but the excluded tire would no longer be required to deliver the rolling-resistance improvement the regulation is intended to produce. 

Tire compromises will mean tradeoffs

Throughout the webinar, Dunlop’s executives consistently brought up that in order for manufacturers to meet California’s new rolling resistance requirements, they will need to sacrifice other crucial performance attributes to meet the standards. Reducing one important characteristic, such as tread depth, could dramatically reduce the tire’s life and overall performance, said Thomas.

“In the event that tread depth is lowered or reduced, two things are also changing: the mileage of the tire and how often they’re replaced,” said Thomas. “All of these tradeoffs are starting to compound on each other.”

When it comes to maintaining proper air pressure of tires, the team said California dealers and drivers can help reduce rolling resistance by complying with air pressure standards.

In DTNA’s proposed hypothetical model of a fleet operating an average of 5 psi below vehicle placard pressure, the company estimated the potential efficiency outcome if the tires were brought to the proper air pressure level. Under the scenario, correcting inflation pressure would represent a modeled gross fuel, energy and CO2 opportunity roughly half the size of the CEC’s rolling-resistance benefit – without requiring major changes to tire engineering, construction or price.

“An advantage for air pressure is that for every 1 psi that the tire is underinflated – from NHTSA data in their TPMS study – it’s a 1.7% loss in mileage,” Brennan pointed out.

The executives highlighted the importance of regulating air pressure as a way to preserve tire longevity and performance for drivers.

What comes next

Since California’s replacement tire efficiency regulation has passed, independent tire dealers and retailers will be tasked with informing consumers on changes with products, availability, costs and efficiency differences of tires. 

To provide an outlet for educating industry stakeholders on how they can prepare their businesses and customers, DTNA is adding a California Replacement Tire Efficiency curriculum to Dunlop Academy, its core training resource. Topics covered in the training will include rolling resistance, tread depth and tire life, wet and worn-wet performance, hydroplaning, tire pressure and TPMS, regulatory exclusions and lifecycle tire economics.

The company will also have tools for consumers designed to help dealers compare purchase price, expected mileage, cost per mile, estimated fuel savings and possible performance implications.

As part of the initiative, the team said Dunlop will work with major tire dealerships and smaller independent retailers to ensure they have the education and tools to best prepare for California’s tire requirements.  

“Dunlop Academy is going to be our commitment – our stewardship – to our dealers, distributors and consumers about how to deal with this subject so the independent tire dealer can take an educated position with consumers to explain low rolling resistance features, benefits and air pressure,” said Thomas.