Motor carriers have endured some difficult times over the past 18 months, but the American Trucking Associations (ATA) believes freight tonnage volumes will continue exhibiting modest growth. Though recovery will be gradual, we expect overall freight tonnage to increase more than 26 percent by 2020, with the modal share moved by truck increasing to 71 percent. The federal government must seriously consider the adoption of more productive trucks to accommodate this large influx of freight demand. ATA supports allowing more productive vehicles - including 6-axle trucks carrying 21 percent more weight than currently allowed - to operate on the Interstate Highway System, consistent with sound engineering standards and safety.

Last June transportation experts from around the world met at the University of Michigan Transportation Research Institute (UMTRI) to discuss a soon-to-be-released study indicating overly restrictive size and weight limits cause the U.S. to lag in truck productivity, safety and environmental sustainability when compared with Europe, Canada, Australia, and Mexico. Bringing our federal regulations more in line with international competitors will reduce logistics costs for businesses and consumers, allowing them to better compete in the global economy. Properly implemented size and weight increases will also improve safety, and reduce emissions.

At present, 6-axle trucks weighing more than 80,000 pounds are used extensively throughout the industrialized world because of their economic, safety and environmental advantages. Many states throughout the U.S. already allow these trucks to operate on secondary roads, and 26 states have grandfather rights that allow them to operate on safer Interstate highways that were designed to handle heavier trucks.

According to UMTRI, class of roadway is the leading factor in truck-involved fatal accidents. Interstates had the lowest accident rate and undivided roads had the highest rate. The UMTRI study also found trucks above 80,000 pounds have a lower fatal accident rate than trucks of less weight.

Our nation's interstates were engineered and constructed for commercial and military use and can handle weights much higher than the current federal restrictions. Interstates are safer than state highways because they are wider, have shoulders, have lesser slopes, and more gradual curves. ATA supports the use of more productive trucks only on roads and bridges that are engineered to handle the load, as determined by State highway departments. By decreasing the number of trucks needed to haul the same amount of freight, more productive trucks lower pavement maintenance costs, mitigate traffic congestion along critical freight corridors and reduce crash exposure.

The Environmental Protection Agency identified the use of more productive trucks as an effective strategy to reduce vehicle emissions as part of its SmartWay Transport Partnership Program. Truck size and weight reform will increase fuel efficiency because fewer trips are needed to deliver the same level of freight. According to the American Transportation Research Institute (ATRI), a 97,000-pound truck is 17 percent more fuel efficient than an 80,000-pound truck when load capacity is factored in.

Today's trucks are already delivering essentials more safely and cleanly than ever before. Truck engines manufactured since 2007 produce at least 90 percent fewer particulate matter emissions than prior engines. Similarly, truck engines manufactured in 2010 produce at least 90 percent fewer nitrogen oxide emissions than prior engines.These advances in diesel emissions control make new diesel trucks the cleanest truck technology available today. Research by the Maine Department of Transportation and ATRI indicates that expanding the federal gross vehicle weight exemptions to additional portions of the Maine Interstate system would allow trucks to be more fuel efficient, resulting in even less particulate matter and nitrogen oxide emissions.