Practical Ways To Improve MPG and Increase Savings

Fuel costs remain the second-largest expense for fleets, just behind labor, and even marginal improvements in fuel economy can translate into meaningful gains in profitability, resiliency and sustainability.

“There has always been a strong industry focus on managing and improving fuel economy, and we’ve seen a lot of companies find success out of continuing to raise the bar in that area,” said Drew Cullen, senior vice president of fuels and facility services at Penske Truck Leasing. “When you improve your fuel economy, reduce idling and eliminate waste within your operation, everybody wins.”

Calculating fuel economy is challenging because an extensive list of variables affects it. Real-world driving conditions vary for every fleet, and fuel efficiency can vary significantly based on various factors unique to each driver and piece of equipment. Model years, vehicle specifications, maintenance, driver behavior, vehicle load weights, terrain and more contribute to the actual miles per gallon fleets achieve.

Key Drivers of Fleet MPG

Penske’s white paper, Advancing Fleet Fuel Efficiency: Enhancing Miles Per Gallon, outlines several practical levers fleets can pull to improve MPG.

Focus on Vehicle Specification

Spec’ing the right equipment for the job is one of the largest single opportunities to improve fuel efficiency. Fleets can optimize fuel efficiency by matching engine displacement, gear ratios, aerodynamics and powertrain features to the duty cycle. Opportunities can include engine downsizing where duty cycles allow, engine downspeeding, which can deliver 2–3% MPG gains, automated manual transmissions, which offer 1–3% MPG improvement, and adaptive cruise control to reduce unnecessary braking and acceleration.

Leverage Aerodynamics

At highway speeds, aerodynamic drag becomes the biggest external force acting on a truck. The white paper shows that modern aerodynamic tractors paired with aerodynamic trailers can exceed 10 MPG, compared with ~6 MPG for older designs — a 40% reduction in fuel and emissions per 100,000 miles. Aerodynamic add-ons include side skirts (1–5%+ savings), trailer tails (5–10% savings), louvered or vented mud flaps and wheel covers.

Maintain Tires and Alignment

Proper tire pressure and alignment are two top maintenance items affecting fuel economy. For example, every 10 psi of under-inflation of tires could create up to a 10% reduction in fuel economy. What’s more, according to the North American Council for Freight Efficiency (NACFE), about one out of five Class 8 tractors and one in five trailers operate with one or more tires underinflated by at least 20 psi.

Additionally, proper alignments are essential to tire performance. “If the alignment isn’t correct, you’ll see where the tractor is not tracking with a trailer. That is not only hard on tires but also on fuel economy,” said Gregg Mangione, executive vice president of maintenance for Penske Truck Leasing.

Reduce Idling Wherever Possible

Idling can consume one gallon of fuel per hour and create greater wear and tear on the engine. NACFE estimates that the average truck idles about 1,000 hours a year, and the Environmental Protection Agency estimates that each year, long-duration truck idling consumes one billion gallons of fuel. APUs, automatic start/stop systems and driver incentives can help reduce idling.

Implement Rigorous Preventive Maintenance

Preventive maintenance can produce 5 to 10% in fuel savings by addressing issues such as exhaust leaks, air leaks, dragging brakes, worn tires, fan operation problems, impaired fuel injectors and more. Something as simple as a malfunctioning engine fan can dramatically degrade MPG.

Train Drivers and Reinforce Behaviors

Driver behavior is often the single largest variable influencing MPG. NACFE estimates that driver behavior alone can swing fuel efficiency by 20% or more. Driver coaching, real-time feedback and speed governors help fleets maintain consistency and reduce wasteful habits

Optimize Routes and Loads

Unnecessary miles waste fuel, capacity and driver time. Route optimization software and dynamic planning can significantly reduce out-of-route miles, while load optimization increases freight efficiency — the amount of freight moved per gallon consumed.

The Benefits of Benchmarking MPG

Although trucks and on-board electronics are generating more data than ever, one of the biggest challenges fleets face is gaining trustworthy, apples-to-apples MPG benchmarks. Fleet applications can vary widely, making comparisons difficult. Catalyst AI™, Penske’s artificial intelligence platform, makes MPG benchmarking more precise, faster and more actionable by comparing fleet operations to similar applications.

Catalyst AI moves beyond fleet averages to pinpoint exact performance variances between vehicles, even among similar specs and duty cycles. It also benchmarks performance by hub, giving operators visibility into site-specific inefficiencies that were previously hidden. That level of detail helps fleets identify underperforming trucks and operating locations, and other opportunities to improve overall fleet performance.

Learn More

Download the Advancing Fleet Fuel Efficiency: Enhancing Miles Per Gallon whitepaper to learn more about the current state of fuel efficiency in the trucking industry, factors affecting the efficiency of fuel and best practices for improving fuel economy. Penske customers and non-customers alike can explore benchmarking opportunities through Catalyst AI.