Certain original equipment exhaust manifolds warp and crack due to lower-grade iron construction. This Dorman OE FIX replacement is made of high-grade ductile iron that better handles heat and stress for greater durability. With over 80 000 products backed by a team of product engineers and experts based in the United States Dorman is the first choice of automotive professionals backyard mechanics and do-it-yourselfers all over North America.