Thought I'd write down some thoughts for the search engine in case anybody is in need of some info.

I've got a 2004 Lariat with a blown motor. I bought a 2008 5.4L Complete engine with like 100 (if that) miles on it from a wrecked truck. Here are the required changes for bolt in.

Fuel rail switched (new fuel rail has no sensor on it)
Oil Pan switch (new pan has no sensor in it)
Air box needed switched, intake and throttle body are good to go.
power steering bracket
new fuel injectors won't fit on old rail (weird)
has regular type spark plugs *SWEET*
needed to use old intake. New intake doesn't have all the vaccuum ports.
needed to use old water pump... new water pump has different fan threads....


Other than that it was straightforward. Also, my old motor was built on February 14th 2004 at 2 am and stamped by Op. 40
New motor was built on Jan 18th 2008 at 10:12 am

 

what happened to the old motor?

 

Well, the ongoing theory is that the timing chain tensioner on the passenger side failed and allowed the chain to skip allowing valve to contact piston.

Honestly, I don't know because the damage was so severe it's hard to tell what the first failure was. Either the timing chain or it dropped a valve. As soon as I peered up past the crank and saw the gaping hole in a piston... and found the valve in the intake manifold, I stopped wondering and ordered a motor. The passenger side timing chain is REALLY loose and the chain guide on that side is gone, but I haven't removed the timing cover.

Either way, it's a motor replacement

J