California tightens tire rules: New standards could save drivers money but eliminate many tires

California regulators have approved new rules that will restrict the sale of replacement tires based on their energy efficiency, with the first phase taking effect in 2029 and stricter standards coming in 2033. The California Energy Commission (CEC) says the rules are intended to reduce fuel and electricity consumption and lower costs for consumers over time.

The standards focus on tire rolling resistance, which measures how much energy a tire consumes as it rolls. The CEC voted unanimously to adopt the rules, which will gradually phase out replacement tires that fail to meet specified efficiency standards.

“This ultimately is about protecting consumers,” CEC Chairman David Hochschild said. “I see this as sheltering the public from higher costs in the long run.”


Under the first phase, beginning in 2029, replacement tires will have to meet a maximum rolling resistance of 9.1 newtons per kilonewton (N/kN). The limit will fall to 7.2 N/kN when the second phase begins in 2033. The standards were developed after the commission tested 537 types of tires.

According to CEC staff, the rules are designed to ensure that replacement tires sold in California are, on average, as energy efficient as tires fitted to new cars and trucks. The commission estimates that consumers could save about $79 in fuel or electricity costs over four months under the first phase. Under the second phase, the estimated savings could reach about $153 over seven months.

“These regulations are a tool within our authority that can save money for every Californian,” Commissioner Nancy Skinner said.

Tire makers raise cost concerns

Tire manufacturers have challenged the commission's assessment of the potential costs. Bret Gladfelty, representing Goodyear, reportedly told the commission that the rules could increase costs for consumers and said technical and legal issues had not been fully resolved.

As reported by KCRA, in a letter to the CEC, Gladfelty also questioned the commission's estimates for the cost of new tires. While the commission expects prices to rise by an average of about $6.50 per tire under the second phase, Gladfelty warned that the increase could reach several hundred dollars per set.

Goodyear and Yokohama have estimated that tires meeting the requirements could cost an additional $6 to $10 each, while manufacturers have warned that some compliant tires could be hundreds of dollars more expensive per set.

Tire manufacturers also estimate that about 70% of tires currently sold in California could fail to meet the standards by 2033. California's own regulatory analysis found that between 82% and 91% of replacement tires could fail to meet the second threshold.

The difference is partly linked to the engineering trade-offs involved in tire design. Tires developed to reduce rolling resistance can affect other characteristics, including wet grip and tread wear.

Bridgestone and Michelin have also raised concerns about enforcement and the possibility of creating an uneven playing field among manufacturers.

CEC staff plan to use a testing laboratory to verify information submitted by tire manufacturers and conduct checks with retailers.

Which tires are exempt?

The rules include several exemptions. They do not apply to competition tires designed for motorsports, winter-type snow tires or all-season winter-performance tires.

Used and retreaded tires, deep-tread tires and tires designed for ATVs and other off-road vehicles are also excluded. Other exemptions cover large off-road tires intended for speeds of up to 99 mph, motorcycle tires and temporary-use spare tires.

Small tires with rim diameters of 13 inches or less, limited-production tires made at fewer than 15,000 units a year, emergency-vehicle tires, tires with a load index of 122 or higher, tires that cannot sustain speeds above 50 mph and space-saver tires are also exempt.

Environmental advocates have backed the regulations, pointing to potential benefits for air quality and reduced energy consumption.

California rule dates back to 2003

The CEC's action stems from Assembly Bill 844, which state lawmakers approved in 2003 and which directed the commission to investigate tire-efficiency regulations.

Hochschild said he was unaware of the legislation until Skinner brought it to his attention. Skinner, who previously served as a California state senator, has authored several laws involving environmental and oil and gas regulation.

When asked whether she had driven the tire rulemaking process, Skinner described it as a collaborative effort among commissioners.

“If I had been on the commission 20 years ago, maybe it wouldn't have taken so long,” she said.

She also suggested that different cost pressures may have contributed to the delay in implementing the legislation.

The CEC has not previously regulated tire efficiency, making California the first US state to introduce such requirements.

CEC Vice Chairman Siva Gunda described the initiative as a partnership with the tire industry and said discussions with manufacturers would continue as the rules take effect.

California standards stricter than Europe

Europe has regulated tire rolling resistance since 2012 under UN Regulation 117. The current limit for passenger-car tires is 10.5 N/kN.

California's first limit of 9.1 N/kN and its second-phase limit of 7.2 N/kN would therefore be stricter than the European threshold. Europe also requires efficiency labels on tires, a system that has not been adopted in the United States.

The CEC estimates that the rules will add about $1.50 per tire during the first phase and $6.50 per tire in the second phase. It estimates fuel savings of about $179 over the life of a set of tires, potentially saving California consumers nearly $1 billion a year.

Tire manufacturers have disputed those estimates, warning that the cost of developing and producing tires that meet the new thresholds could be significantly higher.

The rules reflect the difficulty of balancing rolling resistance with other tire characteristics such as grip and durability. California has included exemptions for several tire categories to account for these differences, while Europe is separately addressing tire-wear particles through its Euro 7 regulations.