The U.S. national average for diesel reached nearly $6.45 per gallon on Friday, a record as oil prices stayed above $100 a barrel and supply constraints drove prices higher across the country. New Jersey and Maine became the latest states to set all-time diesel records, bringing the total to 44, according to GasBuddy head of petroleum analysis Patrick De Haan. De Haan said the national average could soon exceed the inflation-adjusted 2022 peak of $6.58. Gasoline averaged $4.46 per gallon, about 10 cents below its annual peak in May, when U.S.-Iran hostilities lifted oil prices. Regional diesel prices have diverged sharply: West Coast prices exceeded $8 because of taxes, limited refining capacity and import dependence, while Midwest prices approached $7 amid harvest demand and refinery outages. Strategists have speculated about a possible U.S. diesel export ban before the midterm elections if prices remain elevated. The Trump administration issued a 90-day waiver allowing truck drivers transporting gasoline and diesel to work up to 16 hours in a 24-hour period, compared with 14 hours under existing rules, provided required rest breaks are taken. J.B. Hunt expects quarter-to-quarter earnings to decline 5% to 10% as diesel costs rise, while Bank of America analysts said fuel surcharges have struggled to keep pace with seven consecutive weeks of higher diesel prices. Brent crude recently moved above $100 for the first time in two months, and refining constraints and energy bottlenecks linked to the U.S.-Iran conflict have pushed crack spreads (the gap between crude and refined fuel prices) to new highs.