// Field Brief · Week 16
BEHIND THE SHIELD
Fifty days into the Iran conflict, the energy shock that began with the closure of the Strait of Hormuz on March 4 is not fading — it is intensifying. On April 19, U.S. naval forces opened fire on, disabled, and seized an Iranian-flagged cargo vessel attempting to break the blockade near the Strait. Iran has vowed a "swift response," and ceasefire talks that appeared to be gaining traction are now in serious doubt.
The market consequences are direct and measurable. U.S. on-highway diesel averaged $5.61/gal nationally as of April 13 — a 50% increase ($1.89/gal) since the conflict began on February 28. Gulf Arab producers lost 40% of crude output in March alone. The IEA now warns that the Iran war has erased all projected global oil demand growth for 2026, and the supply surplus has collapsed from an expected 2.46 million barrels per day to just 410,000 bpd. There is no meaningful buffer left.
For shippers, the fuel surcharge math has fundamentally changed. Every active lane is now operating under a surcharge table that was written for a different market. If your FSC schedule was set in 2025 or early 2026, it almost certainly does not reflect where diesel is today — or where it is likely to go if the Strait remains restricted.
March freight data from DAT confirmed what the market had been signaling: truckload volumes rose across all equipment types while rates hit their highest levels since early 2024. Dry van spot reached $2.52/mi (up 53 cents year-over-year), reefer spot climbed to $2.97/mi (up 70 cents YoY), and flatbed hit $3.09/mi. Contract rates followed, with van up 20 cents month-over-month to $2.72/mi and reefer up 22 cents to $3.10/mi.
Critically, the Logistics Managers' Index recorded a Transportation Capacity reading of 39.2 in March — the fourth consecutive month of contraction — while Transportation Prices came in at 89.4, a 50.2-point spread that is the widest positive inversion since November 2021. That spread is the single clearest signal that capacity is tightening faster than demand is growing. Tender rejection rates are now running 14–15% nationally and trending higher.
The reefer market remains the tightest segment. With driver supply structurally reduced by the English-language proficiency rule and non-domiciled CDL restrictions, there is no near-term relief valve. C.H. Robinson has raised its 2026 refrigerated van cost forecast to +16% year-over-year.
