Inflation Spreading! US Diesel Breaks $5 per Gallon, Energy Shock Begins Transmitting to Real Economy

U.S. diesel prices this week surpassed $5 per gallon, reaching the highest level since the outbreak of the Russia-Ukraine conflict. The turmoil in the crude oil market caused by attacks on Iran is transmitting through diesel, a core fuel of industrial economies, to a broader real economy.

Unlike the slow decline in gasoline demand, U.S. diesel consumption is almost entirely driven by commercial use—trucking, construction, and industrial production without exception. The rapid price increase is directly eroding the profit margins of countless businesses. The current surge in diesel prices has clearly exceeded that of gasoline, indicating concentrated pressure on supply.

The root cause lies in structural mismatches in crude oil quality. Although the U.S. is the world’s largest oil producer, domestic shale oil is mainly light crude, suitable for refining gasoline; whereas the heavy crude needed for diesel and other distillates mainly comes from the Persian Gulf, Venezuela, and Canada.

According to a previous article by Wall Street Insights, Saudi Arabia has cut crude oil output by about 2 million barrels per day, primarily reducing heavy and medium-heavy crude. Currently, Saudi oil transportation relies on land pipelines through the Red Sea, but these pipelines mainly transport light crude.

Disruption of heavy crude supplies, diesel market faces 2022 crisis logic again

The current surge in diesel prices follows a supply logic highly similar to the situation after the Russia-Ukraine war broke out in 2022. At that time, Western sanctions reduced Russian heavy crude exports, leading to a shortage of heavy feedstock at refineries worldwide; now, Iran’s situation has interrupted the normal flow of Persian Gulf crude, bringing the market back to the same structural dilemma.

Last year, the U.S. imported about 500,000 barrels of Middle Eastern crude daily. As this source has been largely cut off, U.S. refiners are competing for alternative supplies at higher premiums.

Energy giant Phillips 66 announced yesterday that the discount of heavy crude relative to light crude has narrowed again—previously, the discount had widened due to increased flows of Venezuelan oil to North America after the arrest of former Venezuelan President Nicolás Maduro, temporarily supplementing some heavy crude supplies.

Low inventories combined with rising demand have already created a diesel supply-demand gap before the crisis

In fact, even before the U.S.-Israel joint efforts against Iran, the U.S. diesel market was already tight. By 2026, U.S. diesel inventories are expected to be significantly below the ten-year average, with government forecasts indicating inventories will continue to decline over the next two years.

Meanwhile, U.S. diesel demand is still growing, contrasting sharply with the slow decline in gasoline consumption. Since almost all U.S. diesel users are commercial clients, price increases have little buffer, and cost pressures will directly penetrate supply chains at all levels, ultimately passing through to consumers in the form of higher prices.

The key variable in the current situation is when traffic through the Strait of Hormuz will normalize. According to Bloomberg, if shipping traffic cannot improve in the short term, discontent among freight, construction, and manufacturing sectors will continue to rise.

For the market, the real risk is not just the level of oil prices but whether diesel shortages can translate this energy shock into broader inflationary pressures through linked increases in trucking freight costs, building material prices, and industrial goods.