USA STD Front Driveshaft Sport Trac & Mountaineer, 29-5/8" Flange to Center. USA Standard Gear driveshafts are built new from the ground up, not remanufactured, to provide decades of everyday use. All driveshafts arrive fully assembled and ready to install to get your vehicle back on the road quickly.. Get the peace of mind and reliability of a brand-new driveshaft, dont settle for a remanufactured unit. Built fresh from the ground up, USA Standard Gear replacement driveshafts are constructed with high-grade steel, feature new slip yokes, and new maintenance-free u-joints to provide decades of carefree use. In some cases, USA Standard redesigns and strengthens the shaft to exceed factory specs, correcting common OE failure points.