On Friday, April 24, 2026, the California Energy Commission issued its proposed new tire regulations for tires sold in California. The new regulations would require passenger car and light truck tires to meet a maximum rolling resistance level which varies by tire category in 2 phases. The first phase is slated for January 1, 2028, and the second phase on January 1, 2031. The new regulations include a minimum wet grip level. In addition to the tire requirements, tire manufacturers (or brand name owners) would be required to submit data to the CEC on all tires that meet the regulations. Data would include rolling resistance, wet grip level, and enough information to uniquely identify the tire. A database is planned to be available to the public. I go into detail here: https://barrystiretech.com/californ...placement-tire-efficiency-program-april-2026/
Update: Notice of Public Hearing: Notice of Proposed Action: Replacement Tire Efficiency Program Rulemaking
This is a big deal for anyone who wants to boost the fuel economy - lower rolling resistance tires can realistically improve highway MPG by 1-3%, so mandating maximum Crr (rolling resistance coefficient) limits by category should push manufacturers toward compounds that actually help. Curious how they'll handle the wet grip trade-off since lower rolling resistance and high wet traction don't always go hand in hand hopefully the minimum wet grip threshold is set at a meaningful level.
