California adopts new low-rolling-resistance tire standards starting 2029

The California Energy Commission approved a phased rule that will require most replacement tires sold in the state to meet low rolling-resistance standards comparable to the tires originally equipped on new vehicles. The first phase, beginning in 2029, caps rolling resistance at 9.1 newtons per kilonewton (N/kN) and will tighten to 7.2 N/kN in 2033. The commission estimates that the incremental cost to consumers will be about $1.50 per tire in the first phase and $6.50 per tire in the second phase, while a typical gasoline-car driver could save roughly $179 in fuel over the life of a tire set.

The rule includes exemptions for used tires, competition tires, snow tires, motorcycle tires and certain off-road tires limited to 99 mph, leaving the majority of motorists with a reduced selection of compliant tires that are generally more expensive. The commission cited testing with an independent laboratory and real-world treadwear data to argue that the new standards will not shorten tire lifespan.

"In short, these proposed regulations will not result in a shorter replacement tire lifespan for California drivers," the commission said in a statement.

Goodyear challenged the cost estimates, warning that price increases could run into the hundreds of dollars per tire and that technical and legal issues remain unresolved.

"This will increase costs for consumers," Bret Gladfelty of Goodyear told the commission, adding that the agency had not yet resolved several technical and legal concerns.

The regulation also introduces a voluntary "leaf" rating system to indicate tire efficiency, similar to Energy Star labels, though manufacturers may choose whether to display the label.

If adopted by other states, the standards could influence national tire markets, with Washington and Rhode Island reportedly reviewing similar measures.