It,s kinda hard to tell about a deisel. They make so much noise anyhow. I,ve worked on a lot of the older ones before they had electronic engine cotrols & turbo,s. We never had much trouble with the fuel systems but the glow plug systems seem to need work occasonaly. Look for blowby by takeing off the oil cap with the engine running & lisson for huffing puffing noises. If it puts out much black smoke it is overfueling or the air filter is stopped up. Blue smoke is oil burning. Diesel is the way to truck if you are going to do a lot of miles & use. Otherwise gas would be better.
