As the average diesel prices approached $5.401 per gallon during the most recent week ending March 31, the freight market felt it.
During the week of March 22-28, according to the DAT One network, truck posts declined across dry van, reefer, and flatbed. Tighter capacity translated into higher rates, with DAT’s data showing dry van climbed 6 cents to $2.34 per mile, refrigerated 6 cents to $2.75, and flatbed leading the gains at $2.80, up 10 cents on the week.
Meanwhile, Truckstop.com and FTR data for the week ending March 27 told a similar story from a different angle: total load activity surged 4.1% week over week to its highest level since June 2022, while truck postings rose just 0.7%, pushing the Market Demand Index – the ratio of loads to trucks – to its highest point since February 2022.
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Total load posts on DAT edged up 3.99 million for the week, and Truckstop.com and FTR reported that volume ran about 35% higher compared to the same week in 2025, signaling that demand held firm even as available trucks pulled back.
However, Ken Adamo, chief of analytics at DAT Freight & Analytics, noted that rate gains are a “bit of a mirage.”
“It’s empty calories,” Adamo said. “It’s a sweet tooth where rates go up on an all-in basis, and you think that’s great, but it’s actually going up because fuel has gone up… A higher percentage of the carrier’s expense is going to fuel, with less left to pay for the truck, salary, and insurance.”
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In the first three weeks of U.S. military operations against Iran, FTR estimates that fuel costs per mile have risen by about 24 cents at 6 mpg and 21 cents at 7 mpg – the largest three-week increase on record.
The divergence between fuel and rates is worth watching, noted Dean Croke, industry analyst, DAT Freight & Analytics.
“Fuel is up $1.31 per gallon over the past three weeks, but spot linehaul rates are holding steady,” Croke said.
Croke said truckers in response are trimming deadhead miles, looking for lighter loads, and slowing down.
“At current diesel prices, slowing from 75 to 65 mph saves roughly 8 to 9 cents per mile in fuel – the equivalent of a significant per-mile pay raise without hauling a single extra load,” he said. “Carriers are also sitting on the sidelines or declining unprofitable loads, which for brokers increases the urgency of having deep carrier relationships rather than relying on transactional capacity."
The demand side adds another layer of complexity. Flatbed looks strongest, with Adamo pointing to data center construction as a durable driver.
“Data center construction is very robust,” said Jason Miller, professor of supply chain management at the Eli Broad College of Business at Michigan State University. “The solar panels to put in solar fields, the construction equipment – all of this stuff is doing very well right now."
Flatbed loads increased 3.1% to the highest level since May 2022, according to Truckstop.com and FTR data.
Dry van faces more headwinds: furniture, carpet, and appliances are struggling as the housing market stagnates, Miller said, noting that pending home sales are down roughly 40% from 2019 levels.
Croke noted that Manufacturing PMI moved back into expansion territory this year, driven in part by a strong New Orders component, an indicator for freight volumes.
“If PMI growth continues, it would mean a fuel shock is hitting the market just as freight volumes are recovering, a situation that could keep rates elevated even if fuel moderates,” Croke said.
Adamo said he remains cautiously optimistic about how demand is going to hold up come spring shipping season.
"I am terrified of $5-plus diesel through the summer," he said. "I think those things will be at odds with each other, and it’s tension that the system just doesn’t need.”
Regional signals are more mixed. Truckstop.com and FTR reported that flatbed saw double-digit increases (12.7 cents) in every region except the Midwest, and dry van volume rose across the board. Refrigerated loads dipped 5.5% after a strong prior week, with the Midwest accounting for the latest drag.
