The U.S. average for on-highway diesel reached $5.134 per gallon on July 20. At that price, a small difference in where and when a truck fuels can matter, but the biggest savings often begin before the fuel stop. Unnecessary miles and avoidable idle time consume discounted fuel just as effectively as full-price fuel.
A practical fuel plan combines the route, legal hours, delivery window, tank capacity, and network price. Sending a driver far off route for a cheaper gallon can cost more than it saves. So can forcing a stop during a congested period when the same purchase could be made earlier.
Drivers need a plan they can use without being micromanaged. Give them preferred stops, a reasonable backup, the amount to purchase, and a clear exception path when parking, weather, or traffic changes the route. The best policy makes the economical decision easy while leaving room for safety and judgment.
Review exceptions as operating information, not automatic violations. Repeated off-network purchases may reveal a route-plan problem, a fuel-card acceptance issue, or a parking constraint. Fixing the pattern is more valuable than arguing over one receipt.
Fleet Desk analysis based on public agency releases, published operating data, and practical carrier workflows. This is independent editorial analysis, not legal advice or firsthand event reporting.