The ProMaxx Tools Rocky exhaust manifold stud repair tool is designed for technicians removing broken exhaust manifold studs. The Rocky tool, is engineered to handle both two and three valve versions of the 4.6L, 5.4L and 6.8L V-10 Ford gas engines. The device has demonstrated to cut repair times by over 60 percent and nearly eliminate cylinder head removal, even in cases of a broken screw extractor, according to the company.