According to a September 10 post from GasBuddy's head of petroleum analysis Patrick De Haan, five diesel pumps in California are displaying $9.999 a gallon, the maximum figure their hardware can show. This is almost certainly a physical limit rather than a posted rate, similar to older pumps in 2008 that couldn't display prices above $3.99.

California's average diesel price was $7.76 a gallon as of September 9, while the national average reached a new all-time high of $5.97. The price surge is attributed to U.S. refineries running at 98% capacity, disruptions in Iran's Strait of Hormuz, and Ukrainian drone strikes on Russian refineries, all simultaneously crushing diesel supply.