Franklin

Buddys motor was making some bad sounds, it's a 4.5-122K, no mods either, thought for sure it was an injector, but swapped and still the klunking, did a compression test and found 1-5 #450-460, #6 280....so what now? Rebuild? Also I don't do that kind of work anyone got some good places in Phoenix AZ?

2007 5.9

Sounds like either #6 slug is toast or bent valve. Pull the head and check it out...only true way to know how bad the damage is.