Designing Tomorrow’s Truck with Efficiency and Fuel Savings in Mind

Truck designers continuously seek new and better ways to design trucks and allow for added truck equipment that may be incorporated into a truck design to boost fuel efficiency. Such designs may focus on the overall structure of the truck, but also includes equipment such as wheels, tires, and even mudflaps.

Wind Resistance

Wind resistance causes drag. Drag affects fuel efficiency. For years heavy-truck designers have sought improved ways to design trucks with scoops, contours, and body designs that reduce drag and wind resistance as well as help truck owners and operators achieve greater fuel efficiency. Into the future, owners and operators will seek new ways to achieve a greater fuel efficiency, either from the design of the vehicle or from subtle operational practices.

Purdue University, in partnership with Kennesaw University, researched several factors in truck design and operation that could have a significant effect on fuel efficiency. [] They examined numerous areas: idle reduction, chassis design, the rolling resistance of tires, the vehicle's powertrain, tractor aerodynamics, trailer aerodynamics, and operational practices that help boost fuel efficiency.

However, aerodynamics was a principal area of focus as it has a profound effect on fuel efficiency. They noted that great efficiencies have been realized by designing and outfitting trucks with the following parts: aero hoods, fenders and headlamps, aerodynamic bumpers, aerodynamic mirrors, roof fairing, chassis fairings, drive wheel fairings, fifth wheel settings, cab and roof extenders, wheel covers, and vented mud flaps.

Their research showed that the best truck outfitting that can have the greatest impact on fuel efficiency included truck side fairings, gap devices, trailer rear devices that reduce wakes, and a streamlined half body on the top of a trailer.

Importantly, one key point of Purdue's research was adoption. While many truck owners seek fuel efficiency, Purdue says that the earlier you adopt these technologies (the greatest fuel savers as well as others), the sooner you can incrementally start reaping fuel savings. These savings from such fittings are subtle. They're not immediately realized. But over time, and over an entire fleet, savings can add up.

When they looked at potential fuel savings, just by including design modifications that reduce wind resistance and drag, over a period of about 11 years would result in about $9,000 per truck per year. This data was based on research performed from 2003 through 2014. The data is likely to be even more promising now as truck designers have tested designs and adopted even better details in their design to create even greater fuel savings.

They created mock-ups of different designs to prove the fuel savings. For example, a semi-tractor top fairing was modeled. As their research points out, "the device has existed for several years and the design shape has been slightly overlooked. Some of the present fairings are either just on the top of the semi-truck or top and gap. The top cabin and gap have the best optimization for aero flow. However, better aerodynamic flow could be achieved with that same concept but redesigned." Still, the design allowed a boost in efficiency of 6.3 percent.

Lightweight Wheels?

It’s not just wind resistance that leads to fuel savings. Weight also plays a role. When aftermarket parts and equipment are selected that reduce overall weight, without loss of performance, fuel savings may be recognized.

Last year, Maxion Wheels, for example, introduced what they call the “toughest and lightest” standard 22.5x8.25 commercial vehicle steel wheel on the market. Their new design, combined with optimization analysis, eliminated four pounds of material and reduced wheel structural stresses by more than 10 percent.

When the wheels were first introduced to the truck market, the company noted the fuel savings that may be realized with their singular new design. It reduces weight, which translates into fuel savings. “Maxion Wheels’ commitment to leading the commercial vehicle market with cost-competitive lightweight wheels is a key force behind our latest weight reduction breakthrough,” said Donald Polk, president of Maxion Wheels, Americas.. “Improved fuel efficiency and fewer emissions are just two benefits that come from the lighter wheel. Multiply that by 18 and you have a serious top-line payload opportunity and a bottom-line cost benefit.”

A Mixture of Designs Brings the Best Fuel Efficiency

There are so many different parts and designs that contribute to fuel efficiency. The point of them all, however, is that by carefully selecting new and used truck vehicles as part of your fleet, you are able to make small changes to their configuration. Cumulatively, such designs lead to a greater fuel efficiency. And greater fuel efficiency helps truck owners and their drivers be more successful in an environment that is increasingly competitive.