Fleets are benefiting from increased adoption of the latest fuel-saving technologies, but are still falling short of what is possible, according to a new report from the North American Council For Freight Efficiency.

In its latest Annual Fleet Fuel Study, NACFE found that the 20 fleets it surveyed posted a 2% increase in fuel economy from the year before, hitting an average of 7.28 mpg over the course of the year. The 20 fleets are a mix of large- and mid-sized fleets representing 72,000 Class 8 trucks in daycab and sleeper configurations.

This is significantly better than the average reported by the Federal Highway Administration’s most recent data for over-the-road tractors, which shows that fleets made up of older equipment have generally stalled at around 5.9 mpg since it began releasing data in 2007.

NACFE also charted a hypothetical “Business as Usual” prediction, charting what the group would expect these same surveyed fleets to achieve if they had not adopted any fuel-saving technology and only benefited from advances in engine efficiency improvements. These fleets were predicted to achieve 6.42 mpg in the same operating environment, nearly a mile per gallon less.

That gap between “Business as Usual” predictions and NACFE’s surveyed fleets offered savings that weren’t anything to sneeze at. The group said it amounts to $5,122 per year per truck at a $2.65 per gallon cost of with an average tractor mileage of 105,041. In total, NACFE projects that this difference accounts for savings of over $600 million compared to the average.

Compared with the FHWA baseline, savings increase to $8,864 per year per truck.

But despite the gains, NACFE still sees a gap between what these fleets could be achieving and what they are actually seeing. Last year, the group organized the Run on Less challenge, in which fleets placed their best drivers in trucks outfitted with the latest fuel-efficient equipment and managed to average 10.1 mpg in real world driving conditions.

While these results were achieved in an operating environment that placed a premium on fuel-efficient driving at all times, NACFE said fleets need to focus on a comprehensive look at what exactly works for their operations. Simply spec'ing the latest equipment won’t necessarily lead to maximum savings and depending on the typical driving applications, some equipment may be more useful than others.

Good drivers were also seen as a way to increase fuel mileage. While trucks are becoming more technologically advanced, with systems that can increase the efficiency of every driver, a good driver will still be able to get the best out of those systems. While experienced drivers in the past may have had a larger effect on fuel efficiency than they do now, a driver is still an extremely important aspect of it.

The full study goes into more detail on the 85 types of fuel-saving equipment used and even tracks what systems have dropped in adoption since 2016. The report is available for free on the NACFE website.

Corrected to indicate NACFE's Run on Less was last year, not earlier this year. We apologize for the error.