The Peterbilt Model 384 has been recognized as fuel-efficient and environmentally friendly by the Environmental Protection Agency's (EPA) SmartWay program, which establishes a set of fuel-saving, low-emission equipment specifications for new Class 8 long-haul tractors and trailers.

The Model 384 joins Peterbilt Models 387 and 386 as EPA SmartWay-compliant, offering fuel savings of between 10 and 20 percent, lower greenhouse gas emissions, and significantly reduced nitrogen oxides, particulate matter, and other air pollutants.