Truck-maker Western Star -- a division of Daimler Trucks North America -- recently organized a “Serious Trucks” driver challenge at the World of Concrete (WOC) show in Las Vegas earlier this year, with more than 180 competitors with commercial driver’s licenses (CDLs) participating on a closed course designed to gauge their skills at the wheel of two Western Star 4700 series trucks, one equipped with an Allison 4500 RDS transmission and the other with a 10-speed automated manual transmission. All photos courtesy of Western Star.