Extra passenger pounds can cancel out vehicle lightweighting efforts

Americans, on average, have gained enough weight during the past 40 years to cancel out automakers' vehicle-lightweighting efforts such as using lighter components or removing spare tire, reflecting an additional challenge automakers face to meet progressively more strict fuel-economy and greenhouse-gas emissions standards. The information comes from the U.S. Centers for Disease Control and Prevention (CDC) in a recent Automotive News report.

The average adult U.S. male weighs almost 195 pounds, up 28.4 pounds from what an average adult male weighed in 1960, while the average female adult weight has risen 24.5 pounds over the same time period, Automotive News said, citing the CDC. The weight gained by the average male is about the same as a typical tire found on a Ford Mustang and almost cancels out the 30 pounds Ford was able to cut from the 2012 Focus by using a new, six-speed Powershift automatic transmission instead of the old Focus gearbox.

The combined weight gained by the average American male and female can cut average fuel economy by as much as one percent, which could translate to an additional 153 million gallons of gas burned in the U.S. over the course of a year.

Either way, such additional passenger weight offsets some of the advances automakers have made in fuel efficiency in recent years. Last year was the fifth consecutive model year that U.S. fleetwide fuel economy increased, reflecting both more hybrid-electric vehicle sales and improved powertrain technologies. The average 2010 model year car across all makes got 22.5 miles per gallon, up slightly from the 22.4 average for the 2009 model year and about 17 percent higher than the 2004 model year average, the EPA said last November.