For decades, it was simple – the larger the truck, the more emissions and chemicals it discharged into the air. And while that is still the case with a number of medium- and heavy-duty diesel engines, new regulations and state-of-the-art inventions are attempting to improve emission standards. We’ll uncover how fuel efficiency, methods to reduce air pollution and new limits on emissions are transforming the trucking industry.

Transportation Emissions


The largest source of U.S. greenhouse gas emissions comes from the transportation sector. While cars and light-duty trucks cover roughly 60% of emissions, medium- and heavy-duty vehicles make up 23%. This is cause for concern when it comes to figuring out new and innovative ways to reduce emissions amounts, while still keeping up with increasing demand.

Efficiency standards for heavy-duty trucks were established back in 2011. Their purpose includes limiting leakage from vehicle air conditioning systems, as well as nitrous oxide and methane emissions standards. This was taken one step further in 2016, stating heavy-duty trucks will have to develop ways to reduce fuel consumption by 16 percent by 2027.

NOx emission is produced from the reaction of nitrogen and oxygen in the air during combustion, especially at high temperatures. NOx standards and limitations have been phased into federal regulation over the past decade to help reduce the amount of pollutants in the air.

Diesel fueled regulations have also been put in place to substantially limit the amount of sulfur content in on-highway diesel fuel; down from 500 parts-per-million (ppm) to 15 ppm.

Additional provisions to emission standards include a ban on the discharge of crankcase emissions, with the exception of turbocharged or supercharged diesel fueled engines. With a majority of these provisions and regulations already in effect, the long-term goal is to provide more clean, sustainable air for future generations.

Fuel Efficiency

The Environmental Protection Agency was established by President Richard Nixon in 1970 to conduct environmental assessments, research, and education. The EPA also has the ability to impose sanctions, fines and other measures for policy violators. Its Fuel Compliance Program focuses on all parties involved in the distribution system. This includes distributors, carriers, retailers, importers and others – all of whom must certify that combustion and evaporation emissions caused by their source of fuel meets specific requirements set forth by the reformulated gasoline program.

The Clean Fuel Fleet Program requires fleets in cities with significant air quality problems (like Atlanta, Denver, Chicago, and Milwaukee) to incorporate vehicles that will meet clean-fuel emissions standards. These types of fuels include alternative and oxygenated, as well as conventional gasoline.

Preparing for the Future

Several leading companies are continuing to research and develop additional cost-effective ways to increase fuel efficiency in heavy-duty trucks. Various improvements include better equipped diesel engines and transmissions, hybrid innovations, aerodynamic tires, reduced idling capabilities and more.

As these types of improvements continue to make their way from the factories to the roadways, the cost savings could be at an all-time high. Preliminary estimates suggest the nation’s tractor-trailer owners could see annual savings upward of $10 billion over the next several years. The increase of available jobs has the potential to skyrocket as well. Choosing to invest wisely in heavy-duty truck efficiency could create an additional 124,000 jobs by the year 2030.

Additional NOx emission reductions are currently in the works, although they may not be written and announced for a few more years. Research has shown nitrogen oxide emissions are linked to multiple significant health impacts and work to accelerate asthma attacks among a percentage of the population. While the most recent NOx rules have helped reduce those emissions, officials and researchers believe more work can, should and will be done to limit those emissions even further.

Transforming the Trucking Industry

Much like the rest of society, as time goes on, new technology creates opportunities to improve what is already in existence. By continuing to evaluate the trucking industry and focus on limiting harmful emissions, the outlook for a brighter, healthier, and more promising future awaits. To check your emission levels and your engine/exhaust system, stop by one of your local Inland Truck Parts and Service stores for a routine maintenance check.