All Ford exhaust manifolds should last the life span of the vehicle unless it is involved in an accident. This is the engine component that is built to withstand extreme heat and made to last. The exhaust manifold is directly connected to the cylinder heat at its exhaust ports. There is one on your Ford if you have an in-line engine and two if you have a V configured engine. On older model Fords there was nothing placed on the exhaust manifolds. On the new models many of them have a heat shield and sensors for direct input to the onboard computer so the performance of the engine can be properly monitored. The replacement of the Ford exhaust manifold is straight forward. It only becomes complicated when other engine components have to be removed to gain full access to it. The two or three nuts on the stud where the exhaust manifold is connected to the exhaust pipe is also a troublesome area. In most instances the nuts are rusted on and must be heated in order for them to be removed. The new manifold will have new studs in it so there is no worry about damaging the old ones. The mounting of the new exhaust manifold must be done correctly and with care. Just like all other components being connected to the engine, a good seal must be formed. To accomplish this tasks the inner most studs connecting this part to the engine block should be tightened first then alternating front and back working your way outwards. This should occur in a two or three step process. When done correctly your Ford exhaust system will no longer leak robbing your engine of its performance capabilities.