California Becomes First State to Set Efficiency Rules for Replacement Tires, But Track Tires Get a Pass

California has officially become the first state to regulate the efficiency of replacement car tires, following a unanimous vote by the state’s Energy Commission. The rules, first proposed in June, target rolling resistance, the energy lost as a tire deforms while rolling. Replacement tires are often less efficient than factory-installed ones, which can hurt fuel economy or EV range.

California wants replacements to match the average efficiency of original-equipment tires.

The regulations roll out in two phases. 50 per tire. 50 per tire. Despite the upfront cost, the state predicts nearly $1 billion in annual fuel and electricity savings, plus a yearly reduction of two million metric tons of CO2. 60-per-gallon gasoline.

Not everyone is on board. Tire industry representatives have warned of higher costs, enforcement challenges, and cheaper non-compliant imports. According to the New York Times, only about 30 percent of current tires meet the standards California wants by 2033.

Track tires are exempt, following consultations with enthusiast groups, as are large off-road tires, motorcycle tires, and some winter-focused products. However, high-performance summer tires that aren’t extreme enough to qualify as track rubber could face hurdles, and some may disappear from California retailers if manufacturers can’t redesign them economically.

The rule, first considered in 2003, only affects which replacement tires can be sold in the state, not what owners can put on their cars. So no one’s confiscating your weekend tires, and a road trip to Nevada could still bring back boots unavailable at home.