I guess the OE exhaust manifolds on my 5.4L are steel, rather than cast iron. When investigating an exhaust leak, I found one of my manifolds was rusted through! I've never seen this on an OE manifold before. As you can see, the manifold bolts are too rusty to make manifold replacement feasible.
I patched the leak with a high temperature epoxy putty. I don't know how long it will last, but so far, so good.
Sorry, pictures are in reverse order.
I patched the leak with a high temperature epoxy putty. I don't know how long it will last, but so far, so good.
Sorry, pictures are in reverse order.