Even more unlikely to have a 351C built using a '77 casting series truck block. LOL..that casting number told the whole story already.highly unlikely to have a cleveland in an F150 from the factory.
If unreliable means that they are known to be pretty well beat at about 250,00 miles or so..yup..unreliable they are.:toothlessWhile we're on the subject of the 351C vs. The 351M, I've researched them both a little further and am finding that they are more similar than I thought. So is it true that the 351M/400M were unreliable? From what I've read so far that does not seem to be true.