How are fuel prices impacting fleets?
The national average for diesel was $6.53 a gallon on September 21, according to the EIA’s weekly diesel index. That’s the highest on record, past the $5.81 peak from June 2022, and $2.78 more than this time last year. For most fleets, diesel costs are now the most anxiety-inducing number in the budget.
NACFE’s Idle-Reduction Playbook puts a typical Class 8 truck at 1,000 to 1,800 gallons a year burned while idling. If your trucks idle exactly as much as they did last September, that now costs $2,780 to $5,000 more per truck, per year. For a fleet with 500 trucks, that’s $1.39 million to $2.5 million in additional fuel costs. That’s enough to make anyone sweat.
Fleets can do a few things to combat rising fuel costs without spending a ton on massive equipment upgrades. Today, we’re talking about:
- Working with what you have: Make the most of your current systems and equipment.
- Maximizing Operational Efficiency: Tighten routes and schedules
- Expecting more from your equipment: Focus on systems that do more for less.
Let’s dive into it.
How fast will diesel prices come down?
Two things are driving the price up at once. Diesel prices are largely dictated by crude oil prices; the cost of retail, distribution, and taxes; and crack spreads, which show the difference between product and crude oil prices. According to EIA, the world not only has a shortage, but crude oil prices are also high on top of it.
Relief will be slow. EIA expects distillate inventories to stay below the five-year low through much of 2027 and forecasts a 2027 average of $4.40 a gallon. That’s the good-news scenario, and it’s still 74 cents above the diesel average in 2025.
Do fuel surcharges cover fuel burned during idling?
Some fleets have some cushion. A standard fuel surcharge takes the gap between the current EIA diesel price and a contracted base price, divides it by an assumed MPG, and pays it out per mile. That covers most of the fuel a truck burns while hauling. It’s based on last week’s diesel price, though, so when prices climb, you pay the difference until the surcharge catches up.
As we know, a truck idling overnight isn’t moving freight. Those gallons burned produce no miles, so a surcharge that pays by the mile doesn’t pay you back for them. Some fleets don’t have a surcharge to lean on at all. Either way, parked fuel is a cost you carry yourself, and it just keeps getting more expensive.
Slow resets make it worse. When diesel jumped more than 40% in under two months this spring, a modeled 55-truck fleet on a monthly surcharge reset came up about $168,000 short.
So, what can fleets do about record diesel costs?
Work with what you have.
Incentivize drivers by sharing the savings: Drivers constantly make decisions from the cab that affect the fuel bill, and they’re more likely to buy into cost-reduction goals when there’s something in it for them. Pick a few key metrics to target, like idle time, speeding, and harsh braking, to track each week. When there’s progress toward your goals, pay a set share of each month’s fuel savings back to drivers as a cash bonus.
Post the standings visibly and often, so drivers can see where they stand. At $6.53 per gallon of diesel, every gallon of wasted fuel counts. NACFE found the most effective programs combine policy, driver engagement, and technology.
Update your settings for the season: Idle timers, OEM idle management systems, and Idle Smart all run on parameters that need to be adjusted seasonally for optimum savings. Parameters set to fight the July heat may leave a driver freezing in the November cold.
Idle Smart makes it easy to update parameters; you can update everything remotely without ever pulling a truck off the road. Fleets wanting to take the automation further use Smart+ to boost their savings, which adjusts parameters automatically by location and weather for maximum savings and battery protection. PAM Transport’s Director of Fuel put it plainly: “In just one month, we saved an additional $60k in fuel costs and reduced starts by 42%.”
Plan where your trucks fill up: Diesel prices vary widely by region right now. On September 21, EIA had the Lower Atlantic at $6.14 a gallon and the Midwest at $6.68. At these prices, even a 25-cent gap between two stops on the same route is about $37 on a 150-gallon fill. Use the pricing your fuel card network already gives you to plan fill-ups at the cheaper stops. Compare prices before tax, since IFTA settles fuel tax by the miles you drive in each state, not where you buy.
Tighten routes and schedules.
Lanes and schedules set when diesel was $3.75 deserve a second look at $6.53.
- Re-run route optimization. Every extra mile costs about 74% more in fuel than it did a year ago. A few wasted miles per route that weren’t worth fixing last year are definitely worth a second look now.
- Cut deadhead miles. In ATRI’s latest study, truckload fleets with 251 to 1,000 trucks ran 18% of their miles empty, the highest of any size group. With every one-point cut in empty miles saving roughly 115 gallons per truck a year, that’s about $375,000 in potential savings for a 500-truck fleet.
- Move drops and appointments off-peak. Stop-and-go metro traffic at rush hour burns fuel without covering ground. Shift loading and unloading windows to off-peak hours where customers allow it.
When it’s time to upgrade, expect more from your equipment.
APUs are the default answer for a lot of fleets. They manage idling well, but they cost $8,500 to $15,000 per truck, come with their own engine or battery pack to maintain, and, depending on the unit, can still leave trucks exposed to cold starts and dead batteries. With diesel and equipment costs both at record highs, a five-figure purchase per truck that does one main job takes a long time to pay for itself. For some fleets, that $15k price tag (before maintenance) means it’s time to consider other solutions.
Idle Smart costs a fraction of an APU and does more than manage idling and cabin temps. It starts and stops the truck automatically to maintain comfortable cab temperatures for drivers, keep batteries charged, and prevent cold starts, even with the key out or off. Yes, that includes over weekends. NACFE reports fleets using Idle Smart see about $380 per truck per month just in fuel savings, a figure that was reported when diesel averaged $3.81. That’s about 100 gallons per truck each month. At $6.53, that’s about $650 a month, or roughly $7,800 a year per truck.
One 70-truck fleet cut its idle time from 33% to 22% over the past year. That’s about 2,400 gallons of diesel a month. At today’s $6.53, it’s worth roughly $15,500 a month, or more than $186,000 a year. That’s before considering the maintenance savings from preventing dead batteries and cold starts.
3 questions to ask before your 2027 fuel budget review
- What happens to our budget at $5 diesel, and at $6.50? EIA forecasts $4.40 for 2027, but its forecast for this quarter was $5.55, and the pump hit $6.53 twelve days later. Plan a range instead of a single number, and know which projects still make sense at the high end.
- How much are we spending on fuel that can’t be passed on to anyone? Surcharges only pay you back for miles driven with a load. Fuel burned while trucks sit idling, or while they drive empty, gets absorbed. Calculate how much your fleet is spending in this area, and you’ll start to see areas where you can reduce waste internally without touching your rates or spending a pretty penny on new equipment.
- Which fix pays back fastest at today’s price? Rerun every fuel project’s payback at $6.53, including ones you shelved. A project that took 24 months to pay back at 2025’s $3.66 average now pays back in about 13 months.
Will prices come down in 2027?
Prices are expected to drop somewhat, but not as much as we’d probably all hope. EIA expects diesel to average $4.40 next year, which is still well above what fleets paid in 2025.
Thankfully, fleets still have several cost-control levers available without making massive equipment purchases.
Want to see how much you could save with Idle Smart?
How much does idling cost a truck per year at today’s diesel prices?
A typical Class 8 truck burns 1,000 to 1,800 gallons a year idling, according to NACFE. At $6.53 a gallon, that’s about $6,500 to $11,750 per truck, per year, before engine wear.
Why are diesel prices so high right now?
EIA points to two things at once: a worldwide shortage of diesel and high crude oil prices. U.S. diesel inventories are expected to stay below their five-year low through much of 2027.
Do fuel surcharges cover fuel burned while idling?
Usually not. Most surcharges pay per loaded mile, so they don’t cover fuel burned while a truck sits parked and idling. Some trucking fleets don’t have a surcharge at all.
What’s the fastest way for a fleet to cut fuel costs without buying new equipment?
Start with what you already have: share fuel savings with drivers, update idle settings for the season, plan fill-ups at lower-priced stops, and cut empty miles. You can optimize your systems and processes before considering large capital expenditures.
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