Replacing the entire engine is serious overkill for leaking head gaskets. You're better off as far as cost, time, and frustration by just removing the cylinder heads and popping in new gaskets. Have an engine machine shop check the heads for warpage. They can clean them up with the correct scuff pad to provide the correct surface finish for the new gaskets to bite into. You can also have them use a dye to check for cracks if you want to spend more money, but there is no history of those heads cracking on the 4.6L.
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Wednesday, September 18th, 2013 AT 12:27 PM