Truck OEMs are tasked with continually looking for ways to improve the efficiency of their vehicles and reduce their reliance on fuel due to the combined efforts of two government entities to lower the amount of greenhouse gas (GHG) emissions and fuel consumption by heavy duty vehicles on U.S. roadways.
The U.S. Environmental Protection Agency (EPA), an agency of the U.S. federal government tasked with protecting health and the environment (www.epa.gov), and the National Highway Traffic Safety Administration (NHTSA), an agency of the U.S. Department of Transportation responsible for creating and enforcing vehicle safety standards (www.nhtsa.gov), have spearheaded the development of a program for regulating emission standards for heavy duty vehicles. According to the EPA, the proposed standards are expected to lower CO2 emissions by approximately 1 billion metric tons, cut fuel costs by about $170 billion and reduce oil consumption by up to 1.8 billion barrels over the lifetime of the vehicles sold under the program.
Phase I of GHG emissions program, the first-ever set of regulations for medium and heavy duty vehicles, included adopting standards to reduce fuel consumption, CO2 emissions and operating costs for semi tractors, full-size pickup trucks, work vans, vocational vehicles and heavy duty engines. Phase I took effect on vehicles for the 2014 to 2018 model years, while Phase II will cover model years 2021 to 2027.
One means for meeting the standards set forth in the federal regulations is the implementation of 6x2 axle configurations on heavy duty tractors.
“As manufacturers need to meet a growing greenhouse gas regulation, they will want to price 6x2s,” says Mike Roeth, executive director, North American Council for Freight Efficiency (NACFE), a council that serves to provide information to help the efficiency of goods movement in North America (www.nacfe.org).
“When subjected to side-by-side testing by Performance Innovation Transport (PIT) in 2013, 6x2 non-lift axle tractors consistently outperformed the fuel economy of comparably-equipped 6x4 tractors by an average of roughly 3 percent,” says Don Quigley, senior OEM account manager, Link Manufacturing, a provider of cab suspensions and OE engineering support in the development of heavy duty truck suspensions and lift axles (www.linkmfg.com). "But a 6x2 in the pusher position lifts the un-powered Link axle off the road when payloads permit (as much as 50 percent of the time in many applications) the drag/parasitic losses of pulling an unused axle down the road are eliminated, further improving the fuel economy by up to 5 percent when compared with a 6x4 tractor. With current fuel prices, this can save approximately $2,000 in fuel costs per tractor per year."
PIT is a program that offers customized technological solutions and assistance to fleets who want to reduce the cost and environmental impact of their operations or improve operational safety. It is part of FPInnovations, among the largest private scientific research centers in the world (https://fpinnovations.ca).
According to the EPA, fuel efficiency and GHG emissions standards already in place for model years 2014-2018 will result in emissions reductions of 270 million metric tons and save vehicle owners more than $50 billion in fuel costs. The current standards have led to increased sales of model years 2014 and 2015 due in part to improved fuel efficiency.
For more information, visit http://www3.epa.gov/otaq/climate/regs-heavy-duty.htm.
