888-656-7577 Thanks to advanced high-tech materials and assembly processes, the structure in the 2012 Ford Explorer is both lightweight and strong. For starters, the A- and B-pillars are constructed of high-strength boron steel for greatly increased roof crush strength. The front-end support structure features advanced technology, constructed using a lightweight composite (40 percent glass-filled polypropylene with a glass-mat overlay), which matches the lateral stiffness of magnesium while reducing weight.