How to spec your fleet vehicles to maximize fuel mileage

How to spec your fleet vehicles to maximize fuel mileage

Fuel optimization is a concern for most fleet managers and truck drivers. By selecting the right type of engine, focusing on trailer aerodynamics, and utilizing driver- and vehicle-data, fleets can maximize fuel mileage successfully.

According to the 2017 report by the American Transport Research Institute (ATRI), fuel accounts for 30 to 40 percent of a carrier’s Cost Per Mile (CPM). It is second only to driver compensation, which is on a steady rise in an effort to combat the industry-wide driver shortage and high turnover.

Many proven strategies that accomplish higher fuel economy exist, such as effective tire management, driver behavior improvement programs, and proactive vehicle maintenance.

However, for maximum fuel efficiency, carriers should also go the extra mile and “spec” their vehicles for better fuel economy.

Factors to consider before you spec a truck

Before you spec your trucks, remember the following factors:

– Scope of service
Will your drivers operate locally, regionally, or long haul?

– Trailer aerodynamics
The type of trailer you use and trailer aerodynamics also affect fuel consumption and efficiency. According to a report by NACFE, the per-vehicle fuel economy benefit of trailer aerodynamic devices may range from 1% to over 10%.

– Payload
The size and weight of your loads affect the type of engine, transmission, and drive axles you need.

– Special driver requirements
Certain drivers may have specific requirements in order to perform at their best. This includes the transmission types they can operate and the need for a battery Auxiliary Power Unit or APU.

– Route terrain
Ask yourself, what kind of terrain and weather conditions will it traverse?

Understanding cab types

A carrier has three cab style options to choose from:

1. Day cab

A day cab is a reasonable choice if your fleet only operates locally or regionally. These are lighter than cabs that include a sleeper berth.

Due to their weight, day cabs may have good fuel economy right out of the factory. Their shorter wheelbases also offer high maneuverability — perfect in case you need to make urban deliveries.

Day cabs work best with low-profile trailers with low load heights. A roof fairing is typically installed to reduce aerodynamic drag if the trailer is taller than the cab.

2. Mid-roof

Similar to day cabs, mid-roof cabs may also perform efficiently when paired with a low-profile trailer. The only difference between them and day cabs is that the former has a sleeper berth.

Mid-roof cabs should be your first option for regional or long-haul operations. They’re slightly larger and heavier than day cabs but can be a lot smaller and more fuel-efficient than raised-roof cabs with low load heights.

3. Raised roof

A raised roof cab is also designed for regional and long-haul freights.

Its main advantage over mid-roofs is improved aerodynamics with high load heights. However, be mindful of vertical clearance, especially if you need to drive into mills, garages, tunnels, or bridges.

Select the right type of engine

Performance, serviceability, life cycle, and fuel efficiency are all key factors when selecting your engine.

Truck manufacturers offer multiple engine sizes designed for different types of loads.

11- and 12-liter engines are believed to be the most fuel-efficient due to their lightness. However, they lack the horsepower to accommodate heavy loads or reliably travel through rough terrain. 14- to 16-liter engines, on the other hand, pull a lot of extra weight to be efficient if you only carry lightweight loads over flatlands.

In terms of horsepower, heavy-duty operations require ratings between 400 and 600. For other types of loads, a surefire approach is to consult a salesperson for horsepower and torque recommendations.

Aftermarket fuel-saving checklist

Once you’ve chosen your tractors and engines, you can further improve fuel efficiency with some modifications:

  • Concealed exhaust systems
  • Side skirts
  • Trailer skirts
  • Side skirts
  • Aluminum wheels
  • Aluminum frame
  • Wide-base single tires
  • Dual tires during heavy rain, snow, or black ice
  • Horizontal exhaust
  • Aerodynamic wheel covers
  • Aerodynamic side mirrors

The role of a fleet management system in fuel optimization

Lastly, a fleet should be powered by a capable fleet management system that can track inefficient driving habits. This includes hard cornering, excessive acceleration, hard braking, and long idle times.

KeepTruckin has all the fleet management features you need to manage your fleet successfully and increase fuel efficiency.

KeepTruckin ELD Pro users can easily identify inefficient drivers who idle for too long or too frequently. On average, idling a heavy-duty truck consumes about 0.8 gallons of fuel per hour. By identifying, coaching, and monitoring drivers with the KeepTruckin fleet management solution, you can become more fuel efficient.

Within the KeepTruckin Dashboard, you can also view all the information about drivers’ poor driving practices, such as hard acceleration and hard braking. These inefficient driving habits also negatively impact fuel efficiency.

To learn more, click here.

If you have any questions about the KeepTruckin fleet management solution, call 844-325-9230 or email



Jimmy Rodela writes about transportation industry challenges, insights, and compliance news. He specializes in digital media and blogging.

Sign Up Free