The average price of diesel topped its 2022 record high on Friday, spiking to $5.85 per gallon, per AAA. Why it matters: Farmers, truckers and freight companies have been absorbing higher diesel costs since the Iran war began. The ballooning price threatens to further raise shipping costs while compounding a growing political problem for President Trump. It can also indirectly affect households by putting inflationary pressure on anything Americans buy that's carried by truck, which includes a massive share of goods. Driving the news: Diesel has been rising steadily for weeks, but surged 17 cents in just the last two days. The previous record was $5.816, per AAA, set in June 2022. Diesel typically costs more than gasoline because of higher taxes, stricter environmental regulations requiring expensive refining and a lower production yield per barrel of oil. Worth noting: While the strangling of the Strait of Hormuz cast the global market into disarray, Ukraine's highly effective drone campaign targeting Russian refineries has further strained worldwide diesel refinery capacity. "Until that refining supply picture improves, both gasoline and diesel prices face continued upward pressure," Patrick De Haan, head of petroleum analysis at GasBuddy, writes. The diesel crack spread — the price difference between a barrel of crude and the refined product — hit unprecedented triple-digit highs in recent weeks. The big picture: "Diesel is an input to virtually everything we consume," says Erich Muehlegger, an economics professor at the University of California-Davis. Diesel price spikes raise production costs in diesel-dependent industries like fishing, farming and construction. For farmers, it's a double whammy, with the war also driving fertilizer costs higher. The record high price comes as the energy-thirsty peak of harvest season looms for corn and soybeans, the nation's largest farm commodities, Axios' Ben Geman reports. Zoom out: Diesel also fuels the country's trucking fleets. While large carriers like FedEx and UPS have increased their fuel surcharge rates to account for the spiking prices, smaller businesses are more sensitive to volatility. George O'Connor, public affairs director at the Owner-Operator Independent Drivers Association, said in an email to Axios that small business truckers "are the first to feel it when prices jump." Unlike larger competitors, he explained in an email, they can't just raise rates when fuel spikes. Independent truckers, on the other hand, often have less negotiating leverage and work load to load. "With freight rates already low, a sharp increase in diesel can quickly eat up what little margin a small trucking business has left," he added. This time of year, the U.S. would usually see significant increases in diesel inventory ahead of the fall refinery maintenance season, Jason Miller, a professor in supply chain management at Michigan State University, told Axios. "We could be looking at some basically unprecedented low diesel inventories for that time of the year when we start getting into refinery maintenance season." "Lord forbid we have a catastrophic hurricane," Miller said. Reality check: Fuel costs are just a fraction of overall prices consumers see, Muehlegger notes. "But the punchline here is that with higher diesel prices, that's putting upward pressure on prices, and upward pressure ... generally within the economy," he says. Miller previously told Axios that gas prices matter more than diesel for the consumer's pocketbook. But for the overall economy, he says, "diesel matters more." What we're watching: If those price hikes show up in core goods down the line, rather than just retail gasoline or electricity prices, that could make it harder for the Federal Reserve to justify cutting interest rates or even push rates higher. "The Fed is in a box here," John Kilduff, Founding Partner of Again Capital, said recently on CNBC. "They are going to be staring down an inflation pulse now from this renewed price spike." Go deeper: Here's how to understand crude oil costs and what they mean for gas prices